Guide to the Secure Configuration of Fedora

with profile OSPP - Protection Profile for General Purpose Operating Systems
This profile reflects mandatory configuration controls identified in the NIAP Configuration Annex to the Protection Profile for General Purpose Operating Systems (Protection Profile Version 4.2). As Fedora OS is moving target, this profile does not guarantee to provide security levels required from US National Security Systems. Main goal of the profile is to provide Fedora developers with hardened environment similar to the one mandated by US National Security Systems.
This guide presents a catalog of security-relevant configuration settings for Fedora. It is a rendering of content structured in the eXtensible Configuration Checklist Description Format (XCCDF) in order to support security automation. The SCAP content is is available in the scap-security-guide package which is developed at https://www.open-scap.org/security-policies/scap-security-guide.

Providing system administrators with such guidance informs them how to securely configure systems under their control in a variety of network roles. Policy makers and baseline creators can use this catalog of settings, with its associated references to higher-level security control catalogs, in order to assist them in security baseline creation. This guide is a catalog, not a checklist, and satisfaction of every item is not likely to be possible or sensible in many operational scenarios. However, the XCCDF format enables granular selection and adjustment of settings, and their association with OVAL and OCIL content provides an automated checking capability. Transformations of this document, and its associated automated checking content, are capable of providing baselines that meet a diverse set of policy objectives. Some example XCCDF Profiles, which are selections of items that form checklists and can be used as baselines, are available with this guide. They can be processed, in an automated fashion, with tools that support the Security Content Automation Protocol (SCAP). The DISA STIG, which provides required settings for US Department of Defense systems, is one example of a baseline created from this guidance.
Do not attempt to implement any of the settings in this guide without first testing them in a non-operational environment. The creators of this guidance assume no responsibility whatsoever for its use by other parties, and makes no guarantees, expressed or implied, about its quality, reliability, or any other characteristic.

Evaluation Characteristics

Evaluation targetfedora
Benchmark URL#scap_org.open-scap_comp_ssg-fedora-xccdf-1.2.xml
Benchmark IDxccdf_org.ssgproject.content_benchmark_FEDORA
Benchmark version0.1.61
Profile IDxccdf_org.ssgproject.content_profile_ospp
Started at2024-12-29T17:33:19+01:00
Finished at2024-12-29T17:33:56+01:00
Performed byroot
Test systemcpe:/a:redhat:openscap:1.3.5

CPE Platforms

  • cpe:/o:fedoraproject:fedora:36
  • cpe:/o:fedoraproject:fedora:35
  • cpe:/o:fedoraproject:fedora:34
  • cpe:/o:fedoraproject:fedora:33

Addresses

  • IPv4  127.0.0.1
  • IPv4  192.168.0.207
  • IPv6  0:0:0:0:0:0:0:1
  • IPv6  2a02:a311:193:e480:a00:27ff:fe08:80d1
  • IPv6  fe80:0:0:0:a00:27ff:fe08:80d1
  • MAC  00:00:00:00:00:00
  • MAC  08:00:27:08:80:D1

Compliance and Scoring

The target system did not satisfy the conditions of 166 rules! Please review rule results and consider applying remediation.

Rule results

26 passed
166 failed
0 other

Severity of failed rules

0 other
10 low
150 medium
6 high

Score

Scoring systemScoreMaximumPercent
urn:xccdf:scoring:default25.855122100.000000
25.86%

Rule Overview

Group rules by:
TitleSeverityResult
Guide to the Secure Configuration of Fedora 166x fail
System Settings 156x fail
Installing and Maintaining Software 9x fail
System and Software Integrity 4x fail
Software Integrity Checking
Verify Integrity with RPM
Verify File Hashes with RPMhigh
pass
Federal Information Processing Standard (FIPS) 1x fail
Enable FIPS Modehigh
fail
System Cryptographic Policies 2x fail
Configure BIND to use System Crypto Policyhigh
pass
Configure System Cryptography Policyhigh
fail
Configure Kerberos to use System Crypto Policyhigh
pass
Configure Libreswan to use System Crypto Policyhigh
pass
Configure OpenSSL library to use System Crypto Policymedium
fail
Configure SSH to use System Crypto Policymedium
pass
Operating System Vendor Support and Certification 1x fail
The Installed Operating System Is Vendor Supportedhigh
fail
GNOME Desktop Environment
Configure GNOME Screen Locking
Enable GNOME3 Screensaver Idle Activationmedium
notapplicable
Set GNOME3 Screensaver Inactivity Timeoutmedium
notapplicable
Set GNOME3 Screensaver Lock Delay After Activation Periodmedium
notapplicable
Enable GNOME3 Screensaver Lock After Idle Periodmedium
notapplicable
Implement Blank Screensavermedium
notapplicable
Ensure Users Cannot Change GNOME3 Screensaver Settingsmedium
notapplicable
Ensure Users Cannot Change GNOME3 Session Idle Settingsmedium
notapplicable
Make sure that the dconf databases are up-to-date with regards to respective keyfileshigh
notapplicable
Updating Software 5x fail
Install dnf-automatic Packagemedium
fail
Configure dnf-automatic to Install Available Updates Automaticallymedium
fail
Configure dnf-automatic to Install Only Security Updateslow
fail
Ensure Fedora GPG Key Installedhigh
pass
Ensure gpgcheck Enabled In Main dnf Configurationhigh
pass
Ensure gpgcheck Enabled for Local Packageshigh
fail
Ensure gpgcheck Enabled for All dnf Package Repositorieshigh
pass
Enable dnf-automatic Timermedium
fail
Account and Access Control 15x fail
Warning Banners for System Accesses 1x fail
Enable GNOME3 Login Warning Bannermedium
notapplicable
Modify the System Login Bannermedium
fail
Protect Accounts by Configuring PAM 10x fail
Set Lockouts for Failed Password Attempts 4x fail
Lock Accounts After Failed Password Attemptsmedium
fail
Configure the root Account for Failed Password Attemptsmedium
fail
Set Interval For Counting Failed Password Attemptsmedium
fail
Set Lockout Time for Failed Password Attemptsmedium
fail
Set Password Quality Requirements 6x fail
Set Password Quality Requirements with pam_pwquality 6x fail
Ensure PAM Enforces Password Requirements - Minimum Digit Charactersmedium
fail
Ensure PAM Enforces Password Requirements - Minimum Lowercase Charactersmedium
fail
Ensure PAM Enforces Password Requirements - Minimum Lengthmedium
fail
Ensure PAM Enforces Password Requirements - Minimum Special Charactersmedium
fail
Ensure PAM Enforces Password Requirements - Authentication Retry Prompts Permitted Per-Sessionmedium
fail
Ensure PAM Enforces Password Requirements - Minimum Uppercase Charactersmedium
fail
Protect Physical Console Access 1x fail
Configure Screen Locking 1x fail
Configure Console Screen Locking 1x fail
Install the screen Packagemedium
fail
Disable debug-shell SystemD Servicemedium
pass
Verify that Interactive Boot is Disabledmedium
pass
Require Authentication for Single User Modemedium
pass
Protect Accounts by Restricting Password-Based Login 2x fail
Set Password Expiration Parameters 1x fail
Set Password Minimum Length in login.defsmedium
fail
Verify Proper Storage and Existence of Password Hashes 1x fail
Prevent Login to Accounts With Empty Passwordhigh
fail
Secure Session Configuration Files for Login Accounts 1x fail
Set Interactive Session Timeoutmedium
fail
System Accounting with auditd 107x fail
Configure auditd Rules for Comprehensive Auditing 101x fail
Record Events that Modify the System's Discretionary Access Controls 13x fail
Record Events that Modify the System's Discretionary Access Controls - chmodmedium
fail
Record Events that Modify the System's Discretionary Access Controls - chownmedium
fail
Record Events that Modify the System's Discretionary Access Controls - fchmodmedium
fail
Record Events that Modify the System's Discretionary Access Controls - fchmodatmedium
fail
Record Events that Modify the System's Discretionary Access Controls - fchownmedium
fail
Record Events that Modify the System's Discretionary Access Controls - fchownatmedium
fail
Record Events that Modify the System's Discretionary Access Controls - fremovexattrmedium
fail
Record Events that Modify the System's Discretionary Access Controls - fsetxattrmedium
fail
Record Events that Modify the System's Discretionary Access Controls - lchownmedium
fail
Record Events that Modify the System's Discretionary Access Controls - lremovexattrmedium
fail
Record Events that Modify the System's Discretionary Access Controls - lsetxattrmedium
fail
Record Events that Modify the System's Discretionary Access Controls - removexattrmedium
fail
Record Events that Modify the System's Discretionary Access Controls - setxattrmedium
fail
Record Execution Attempts to Run SELinux Privileged Commands 5x fail
Record Any Attempts to Run chconmedium
fail
Record Any Attempts to Run restoreconmedium
fail
Record Any Attempts to Run semanagemedium
fail
Record Any Attempts to Run setseboolmedium
fail
Record Any Attempts to Run seunsharemedium
fail
Record File Deletion Events by User 5x fail
Ensure auditd Collects File Deletion Events by User - renamemedium
fail
Ensure auditd Collects File Deletion Events by User - renameatmedium
fail
Ensure auditd Collects File Deletion Events by User - rmdirmedium
fail
Ensure auditd Collects File Deletion Events by User - unlinkmedium
fail
Ensure auditd Collects File Deletion Events by User - unlinkatmedium
fail
Record Unauthorized Access Attempts Events to Files (unsuccessful) 32x fail
Record Unsuccessul Permission Changes to Files - chmodmedium
fail
Record Unsuccessul Ownership Changes to Files - chownmedium
fail
Record Unsuccessful Access Attempts to Files - creatmedium
fail
Record Unsuccessul Permission Changes to Files - fchmodmedium
fail
Record Unsuccessul Permission Changes to Files - fchmodatmedium
fail
Record Unsuccessul Ownership Changes to Files - fchownmedium
fail
Record Unsuccessul Ownership Changes to Files - fchownatmedium
fail
Record Unsuccessul Permission Changes to Files - fremovexattrmedium
fail
Record Unsuccessul Permission Changes to Files - fsetxattrmedium
fail
Record Unsuccessful Access Attempts to Files - ftruncatemedium
fail
Record Unsuccessul Ownership Changes to Files - lchownmedium
fail
Record Unsuccessul Permission Changes to Files - lremovexattrmedium
fail
Record Unsuccessul Permission Changes to Files - lsetxattrmedium
fail
Record Unsuccessful Access Attempts to Files - openmedium
fail
Record Unsuccessful Access Attempts to Files - open_by_handle_atmedium
fail
Record Unsuccessful Creation Attempts to Files - open_by_handle_at O_CREATmedium
fail
Record Unsuccessful Modification Attempts to Files - open_by_handle_at O_TRUNC_WRITEmedium
fail
Ensure auditd Unauthorized Access Attempts To open_by_handle_at Are Ordered Correctlymedium
fail
Record Unsuccessful Creation Attempts to Files - open O_CREATmedium
fail
Record Unsuccessful Modification Attempts to Files - open O_TRUNC_WRITEmedium
fail
Ensure auditd Rules For Unauthorized Attempts To open Are Ordered Correctlymedium
fail
Record Unsuccessful Access Attempts to Files - openatmedium
fail
Record Unsuccessful Creation Attempts to Files - openat O_CREATmedium
fail
Record Unsuccessful Modification Attempts to Files - openat O_TRUNC_WRITEmedium
fail
Ensure auditd Rules For Unauthorized Attempts To openat Are Ordered Correctlymedium
fail
Record Unsuccessul Permission Changes to Files - removexattrmedium
fail
Record Unsuccessul Delete Attempts to Files - renamemedium
fail
Record Unsuccessul Delete Attempts to Files - renameatmedium
fail
Record Unsuccessul Permission Changes to Files - setxattrmedium
fail
Record Unsuccessful Access Attempts to Files - truncatemedium
fail
Record Unsuccessul Delete Attempts to Files - unlinkmedium
fail
Record Unsuccessul Delete Attempts to Files - unlinkatmedium
fail
Record Information on Kernel Modules Loading and Unloading 2x fail
Ensure auditd Collects Information on Kernel Module Unloading - delete_modulemedium
fail
Ensure auditd Collects Information on Kernel Module Loading - init_modulemedium
fail
Record Attempts to Alter Logon and Logout Events - faillockmedium
fail
Record Attempts to Alter Logon and Logout Events - lastlogmedium
fail
Record Attempts to Alter Logon and Logout Events - tallylogmedium
fail
Record Information on the Use of Privileged Commands 19x fail
Ensure auditd Collects Information on the Use of Privileged Commands - atmedium
fail
Ensure auditd Collects Information on the Use of Privileged Commands - chagemedium
fail
Ensure auditd Collects Information on the Use of Privileged Commands - chshmedium
fail
Ensure auditd Collects Information on the Use of Privileged Commands - crontabmedium
fail
Ensure auditd Collects Information on the Use of Privileged Commands - gpasswdmedium
fail
Ensure auditd Collects Information on the Use of Privileged Commands - mountmedium
fail
Ensure auditd Collects Information on the Use of Privileged Commands - newgidmapmedium
fail
Ensure auditd Collects Information on the Use of Privileged Commands - newgrpmedium
fail
Ensure auditd Collects Information on the Use of Privileged Commands - newuidmapmedium
fail
Ensure auditd Collects Information on the Use of Privileged Commands - passwdmedium
fail
Ensure auditd Collects Information on the Use of Privileged Commands - pt_chownmedium
fail
Ensure auditd Collects Information on the Use of Privileged Commands - ssh-keysignmedium
fail
Ensure auditd Collects Information on the Use of Privileged Commands - sumedium
fail
Ensure auditd Collects Information on the Use of Privileged Commands - sudomedium
fail
Ensure auditd Collects Information on the Use of Privileged Commands - sudoeditmedium
fail
Ensure auditd Collects Information on the Use of Privileged Commands - umountmedium
fail
Ensure auditd Collects Information on the Use of Privileged Commands - unix_chkpwdmedium
fail
Ensure auditd Collects Information on the Use of Privileged Commands - userhelpermedium
fail
Ensure auditd Collects Information on the Use of Privileged Commands - usernetctlmedium
fail
Record Events that Modify User/Group Information via open syscall - /etc/groupmedium
fail
Record Events that Modify User/Group Information via open_by_handle_at syscall - /etc/groupmedium
fail
Record Events that Modify User/Group Information via openat syscall - /etc/groupmedium
fail
Record Events that Modify User/Group Information via open syscall - /etc/gshadowmedium
fail
Record Events that Modify User/Group Information via open_by_handle_at syscall - /etc/gshadowmedium
fail
Record Events that Modify User/Group Information via openat syscall - /etc/gshadowmedium
fail
Record Events that Modify User/Group Information via open syscall - /etc/passwdmedium
fail
Record Events that Modify User/Group Information via open_by_handle_at syscall - /etc/passwdmedium
fail
Record Events that Modify User/Group Information via openat syscall - /etc/passwdmedium
fail
Record Events that Modify User/Group Information via open syscall - /etc/shadowmedium
fail
Record Events that Modify User/Group Information via open_by_handle_at syscall - /etc/shadowmedium
fail
Record Events that Modify User/Group Information via openat syscall - /etc/shadowmedium
fail
Make the auditd Configuration Immutablemedium
fail
Record Events that Modify the System's Mandatory Access Controlsmedium
fail
Record Attempts to Alter Process and Session Initiation Informationmedium
fail
Ensure auditd Collects System Administrator Actionsmedium
fail
Record Events that Modify User/Group Information - /etc/groupmedium
fail
Record Events that Modify User/Group Information - /etc/gshadowmedium
fail
Record Events that Modify User/Group Information - /etc/security/opasswdmedium
fail
Record Events that Modify User/Group Information - /etc/passwdmedium
fail
Record Events that Modify User/Group Information - /etc/shadowmedium
fail
Record Access Events to Audit Log Directorymedium
fail
Configure auditd Data Retention 4x fail
Configure audispd Plugin To Send Logs To Remote Servermedium
fail
Encrypt Audit Records Sent With audispd Pluginmedium
fail
Configure auditd to use audispd's syslog pluginmedium
fail
Set number of records to cause an explicit flush to audit logsmedium
pass
Include Local Events in Audit Logsmedium
pass
Resolve information before writing to audit logsmedium
pass
Set hostname as computer node name in audit logsmedium
fail
Write Audit Logs to the Diskmedium
pass
Enable Auditing for Processes Which Start Prior to the Audit Daemonmedium
fail
Extend Audit Backlog Limit for the Audit Daemonlow
fail
GRUB2 bootloader configuration 3x fail
Non-UEFI GRUB2 bootloader configuration 1x fail
Set Boot Loader Password in grub2high
fail
UEFI GRUB2 bootloader configuration
Set the UEFI Boot Loader Passwordhigh
notapplicable
Enable Kernel Page-Table Isolation (KPTI)low
fail
Disable vsyscallsmedium
fail
Configure Syslog 1x fail
Ensure Proper Configuration of Log Files
Ensure cron Is Logging To Rsyslogmedium
pass
Rsyslog Logs Sent To Remote Host 1x fail
Ensure Logs Sent To Remote Hostmedium
fail
Network Configuration and Firewalls 5x fail
firewalld 1x fail
Inspect and Activate Default firewalld Rules
Verify firewalld Enabledmedium
pass
Strengthen the Default Ruleset 1x fail
Set Default firewalld Zone for Incoming Packetsmedium
fail
Uncommon Network Protocols 4x fail
Disable ATM Supportmedium
fail
Disable CAN Supportmedium
fail
Disable IEEE 1394 (FireWire) Supportlow
fail
Disable TIPC Supportlow
fail
File Permissions and Masks 15x fail
Restrict Partition Mount Options 1x fail
Add nodev Option to /dev/shmmedium
pass
Add noexec Option to /dev/shmmedium
fail
Add nosuid Option to /dev/shmmedium
pass
Restrict Programs from Dangerous Execution Patterns 14x fail
Disable Core Dumps 3x fail
Disable acquiring, saving, and processing core dumpsmedium
fail
Disable core dump backtracesmedium
fail
Disable storing core dumpmedium
fail
Enable ExecShield 1x fail
Restrict Exposed Kernel Pointer Addresses Accessmedium
fail
Memory Poisoning 2x fail
Enable page allocator poisoningmedium
fail
Enable SLUB/SLAB allocator poisoningmedium
fail
Disable storing core dumpsmedium
fail
Restrict Access to Kernel Message Bufferlow
fail
Disable Kernel Image Loadingmedium
fail
Disallow kernel profiling by unprivileged userslow
fail
Disable Access to Network bpf() Syscall From Unprivileged Processesmedium
fail
Restrict usage of ptrace to descendant processesmedium
fail
Harden the operation of the BPF just-in-time compilermedium
fail
Disable the use of user namespacesmedium
fail
SELinux 1x fail
Ensure No Device Files are Unlabeled by SELinuxmedium
fail
Ensure No Daemons are Unconfined by SELinuxmedium
pass
Configure SELinux Policymedium
pass
Ensure SELinux State is Enforcingmedium
pass
Services 10x fail
Base Services 1x fail
Uninstall Automatic Bug Reporting Tool (abrt)medium
fail
Application Whitelisting Daemon 1x fail
Install fapolicyd Packagemedium
fail
Mail Server Software
Uninstall Sendmail Packagemedium
pass
Network Time Protocol 2x fail
Disable chrony daemon from acting as serverlow
fail
Disable network management of chrony daemonlow
fail
Hardware RNG Entropy Gatherer Daemon 1x fail
Enable the Hardware RNG Entropy Gatherer Servicelow
fail
SSH Server 4x fail
Configure OpenSSH Server if Necessary 4x fail
Disable Host-Based Authenticationmedium
pass
Disable SSH Access via Empty Passwordshigh
pass
Disable GSSAPI Authenticationmedium
fail
Disable Kerberos Authenticationmedium
pass
Disable SSH Root Loginmedium
fail
Enable SSH Warning Bannermedium
fail
Force frequent session key renegotiationmedium
fail
System Security Services Daemon 1x fail
Configure SSSD to run as user sssdmedium
fail

Result Details

Verify File Hashes with RPMxccdf_org.ssgproject.content_rule_rpm_verify_hashes high

Verify File Hashes with RPM

Rule IDxccdf_org.ssgproject.content_rule_rpm_verify_hashes
Result
pass
Multi-check ruleno
OVAL Definition IDoval:ssg-rpm_verify_hashes:def:1
Time2024-12-29T17:33:54+01:00
Severityhigh
Identifiers and References

References:  11, 2, 3, 9, 5.10.4.1, APO01.06, BAI03.05, BAI06.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS06.02, 3.3.8, 3.4.1, CCI-000366, CCI-001749, 164.308(a)(1)(ii)(D), 164.312(b), 164.312(c)(1), 164.312(c)(2), 164.312(e)(2)(i), 4.3.4.3.2, 4.3.4.3.3, 4.3.4.4.4, SR 3.1, SR 3.3, SR 3.4, SR 3.8, SR 7.6, A.11.2.4, A.12.1.2, A.12.2.1, A.12.5.1, A.12.6.2, A.14.1.2, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4, CM-6(d), CM-6(c), SI-7, SI-7(1), SI-7(6), AU-9(3), PR.DS-6, PR.DS-8, PR.IP-1, Req-11.5, SRG-OS-000480-GPOS-00227

Description
Without cryptographic integrity protections, system executables and files can be altered by unauthorized users without detection. The RPM package management system can check the hashes of installed software packages, including many that are important to system security. To verify that the cryptographic hash of system files and commands matches vendor values, run the following command to list which files on the system have hashes that differ from what is expected by the RPM database:
$ rpm -Va --noconfig | grep '^..5'
A "c" in the second column indicates that a file is a configuration file, which may appropriately be expected to change. If the file was not expected to change, investigate the cause of the change using audit logs or other means. The package can then be reinstalled to restore the file. Run the following command to determine which package owns the file:
$ rpm -qf FILENAME
The package can be reinstalled from a dnf repository using the command:
$ sudo dnf reinstall PACKAGENAME
Alternatively, the package can be reinstalled from trusted media using the command:
$ sudo rpm -Uvh PACKAGENAME
Rationale
The hashes of important files like system executables should match the information given by the RPM database. Executables with erroneous hashes could be a sign of nefarious activity on the system.
OVAL test results details

verify file md5 hashes  oval:ssg-test_files_fail_md5_hash:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-object_files_fail_md5_hash:obj:1 of type rpmverifyfile_object
BehaviorsNameEpochVersionReleaseArchFilepathFilter
no value.*.*.*.*.*^/(bin|sbin|lib|lib64|usr)/.+$oval:ssg-state_files_fail_md5_hash:ste:1
Enable FIPS Modexccdf_org.ssgproject.content_rule_enable_fips_mode high

Enable FIPS Mode

Rule IDxccdf_org.ssgproject.content_rule_enable_fips_mode
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-enable_fips_mode:def:1
Time2024-12-29T17:33:54+01:00
Severityhigh
Identifiers and References

References:  CCI-000068, CCI-000803, CCI-002450, 1446, CIP-003-8 R4.2, CIP-007-3 R5.1, SC-12(2), SC-12(3), IA-7, SC-13, CM-6(a), SC-12, FCS_COP.1(1), FCS_COP.1(2), FCS_COP.1(3), FCS_COP.1(4), FCS_CKM.1, FCS_CKM.2, FCS_TLSC_EXT.1, FCS_RBG_EXT.1, SRG-OS-000478-GPOS-00223, SRG-OS-000396-GPOS-00176, SRG-OS-000120-VMM-000600, SRG-OS-000478-VMM-001980, SRG-OS-000396-VMM-001590

Description
To enable FIPS mode, run the following command:
fips-mode-setup --enable

The fips-mode-setup command will configure the system in FIPS mode by automatically configuring the following:
  • Setting the kernel FIPS mode flag (/proc/sys/crypto/fips_enabled) to 1
  • Creating /etc/system-fips
  • Setting the system crypto policy in /etc/crypto-policies/config to FIPS
  • Loading the Dracut fips module
Rationale
Use of weak or untested encryption algorithms undermines the purposes of utilizing encryption to protect data. The operating system must implement cryptographic modules adhering to the higher standards approved by the federal government since this provides assurance they have been tested and validated.
Warnings
warning  The system needs to be rebooted for these changes to take effect.
warning  This rule DOES NOT CHECK if the components of the operating system are FIPS certified. You can find the list of FIPS certified modules at https://csrc.nist.gov/projects/cryptographic-module-validation-program/validated-modules/search. This rule checks if the system is running in FIPS mode. See the rule description for more information about what it means.

# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

var_system_crypto_policy='FIPS'


fips-mode-setup --enable

stderr_of_call=$(update-crypto-policies --set ${var_system_crypto_policy} 2>&1 > /dev/null)
rc=$?

if test "$rc" = 127; then
	echo "$stderr_of_call" >&2
	echo "Make sure that the script is installed on the remediated system." >&2
	echo "See output of the 'dnf provides update-crypto-policies' command" >&2
	echo "to see what package to (re)install" >&2

	false  # end with an error code
elif test "$rc" != 0; then
	echo "Error invoking the update-crypto-policies script: $stderr_of_call" >&2
	false  # end with an error code
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:medium
Disruption:medium
Reboot:true
Strategy:restrict
- name: XCCDF Value var_system_crypto_policy # promote to variable
  set_fact:
    var_system_crypto_policy: !!str FIPS
  tags:
    - always

- name: Check to see the current status of FIPS mode
  command: /usr/bin/fips-mode-setup --check
  register: is_fips_enabled
  changed_when: false
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-CM-6(a)
    - NIST-800-53-IA-7
    - NIST-800-53-SC-12
    - NIST-800-53-SC-12(2)
    - NIST-800-53-SC-12(3)
    - NIST-800-53-SC-13
    - enable_fips_mode
    - high_severity
    - medium_complexity
    - medium_disruption
    - reboot_required
    - restrict_strategy

- name: Enable FIPS mode
  command: /usr/bin/fips-mode-setup --enable
  when:
    - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
    - is_fips_enabled.stdout.find('FIPS mode is enabled.') == -1
  tags:
    - NIST-800-53-CM-6(a)
    - NIST-800-53-IA-7
    - NIST-800-53-SC-12
    - NIST-800-53-SC-12(2)
    - NIST-800-53-SC-12(3)
    - NIST-800-53-SC-13
    - enable_fips_mode
    - high_severity
    - medium_complexity
    - medium_disruption
    - reboot_required
    - restrict_strategy

- name: Enable FIPS Mode
  lineinfile:
    path: /etc/crypto-policies/config
    regexp: ^(?!#)(\S+)$
    line: '{{ var_system_crypto_policy }}'
    create: true
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-CM-6(a)
    - NIST-800-53-IA-7
    - NIST-800-53-SC-12
    - NIST-800-53-SC-12(2)
    - NIST-800-53-SC-12(3)
    - NIST-800-53-SC-13
    - enable_fips_mode
    - high_severity
    - medium_complexity
    - medium_disruption
    - reboot_required
    - restrict_strategy

- name: Verify that Crypto Policy is Set (runtime)
  command: /usr/bin/update-crypto-policies --set {{ var_system_crypto_policy }}
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-CM-6(a)
    - NIST-800-53-IA-7
    - NIST-800-53-SC-12
    - NIST-800-53-SC-12(2)
    - NIST-800-53-SC-12(3)
    - NIST-800-53-SC-13
    - enable_fips_mode
    - high_severity
    - medium_complexity
    - medium_disruption
    - reboot_required
    - restrict_strategy
OVAL test results details

/etc/system-fips exists  oval:ssg-test_etc_system_fips:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_etc_system_fips:obj:1 of type file_object
Filepath
/etc/system-fips

kernel runtime parameter crypto.fips_enabled set to 1  oval:ssg-test_sysctl_crypto_fips_enabled:tst:1  false

Following items have been found on the system:
NameValue
crypto.fips_enabled0

add_dracutmodules contains fips  oval:ssg-test_enable_dracut_fips_module:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_enable_dracut_fips_module:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/dracut.conf.d/40-fips.conf^\s*add_dracutmodules\+="\s*(\w*)\s*"\s*(?:#.*)?$1

check for crypto policy correctly configured in /etc/crypto-policies/config  oval:ssg-test_configure_crypto_policy:tst:1  false

Following items have been found on the system:
PathContent
/etc/crypto-policies/configDEFAULT

check for crypto policy correctly configured in /etc/crypto-policies/state/current  oval:ssg-test_configure_crypto_policy_current:tst:1  false

Following items have been found on the system:
PathContent
/etc/crypto-policies/state/currentDEFAULT

Check if update-crypto-policies has been run  oval:ssg-test_crypto_policies_updated:tst:1  true

Following items have been found on the system:
Var refValue
oval:ssg-variable_crypto_policies_config_file_timestamp:var:11735487419

Check if /etc/crypto-policies/back-ends/nss.config exists  oval:ssg-test_crypto_policy_nss_config:tst:1  true

Following items have been found on the system:
PathTypeUIDGIDSize (B)Permissions
/etc/crypto-policies/back-ends/nss.configregular00447rw-r--r-- 

tests if var_system_crypto_policy is set to FIPS  oval:ssg-test_system_crypto_policy_value:tst:1  true

Following items have been found on the system:
Var refValue
oval:ssg-var_system_crypto_policy:var:1FIPS
Configure BIND to use System Crypto Policyxccdf_org.ssgproject.content_rule_configure_bind_crypto_policy high

Configure BIND to use System Crypto Policy

Rule IDxccdf_org.ssgproject.content_rule_configure_bind_crypto_policy
Result
pass
Multi-check ruleno
OVAL Definition IDoval:ssg-configure_bind_crypto_policy:def:1
Time2024-12-29T17:33:54+01:00
Severityhigh
Identifiers and References

References:  CIP-003-8 R4.2, CIP-007-3 R5.1, SC-13, SC-12(2), SC-12(3), SRG-OS-000423-GPOS-00187, SRG-OS-000426-GPOS-00190

Description
Crypto Policies provide a centralized control over crypto algorithms usage of many packages. BIND is supported by crypto policy, but the BIND configuration may be set up to ignore it. To check that Crypto Policies settings are configured correctly, ensure that the /etc/named.conf includes the appropriate configuration: In the options section of /etc/named.conf, make sure that the following line is not commented out or superseded by later includes: include "/etc/crypto-policies/back-ends/bind.config";
Rationale
Overriding the system crypto policy makes the behavior of the BIND service violate expectations, and makes system configuration more fragmented.
OVAL test results details

package bind is removed  oval:ssg-test_package_bind_removed:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-obj_test_package_bind_removed:obj:1 of type rpminfo_object
Name
bind

Check that the configuration includes the policy config file.  oval:ssg-test_configure_bind_crypto_policy:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_configure_bind_crypto_policy:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/named.conf^\s*include\s+"/etc/crypto-policies/back-ends/bind.config"\s*;\s*$1
Configure System Cryptography Policyxccdf_org.ssgproject.content_rule_configure_crypto_policy high

Configure System Cryptography Policy

Rule IDxccdf_org.ssgproject.content_rule_configure_crypto_policy
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-configure_crypto_policy:def:1
Time2024-12-29T17:33:54+01:00
Severityhigh
Identifiers and References

References:  164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.312(e)(1), 164.312(e)(2)(ii), 1446, CIP-003-8 R4.2, CIP-007-3 R5.1, CIP-007-3 R7.1, AC-17(a), AC-17(2), CM-6(a), MA-4(6), SC-13, SC-12(2), SC-12(3), FCS_COP.1(1), FCS_COP.1(2), FCS_COP.1(3), FCS_COP.1(4), FCS_CKM.1, FCS_CKM.2, FCS_TLSC_EXT.1, SRG-OS-000396-GPOS-00176, SRG-OS-000393-GPOS-00173, SRG-OS-000394-GPOS-00174

Description
To configure the system cryptography policy to use ciphers only from the FIPS policy, run the following command:
$ sudo update-crypto-policies --set FIPS
The rule checks if settings for selected crypto policy are configured as expected. Configuration files in the /etc/crypto-policies/back-ends are either symlinks to correct files provided by Crypto-policies package or they are regular files in case crypto policy customizations are applied. Crypto policies may be customized by crypto policy modules, in which case it is delimited from the base policy using a colon.
Rationale
Centralized cryptographic policies simplify applying secure ciphers across an operating system and the applications that run on that operating system. Use of weak or untested encryption algorithms undermines the purposes of utilizing encryption to protect data.
Warnings
warning  The system needs to be rebooted for these changes to take effect.
warning  System Crypto Modules must be provided by a vendor that undergoes FIPS-140 certifications. FIPS-140 is applicable to all Federal agencies that use cryptographic-based security systems to protect sensitive information in computer and telecommunication systems (including voice systems) as defined in Section 5131 of the Information Technology Management Reform Act of 1996, Public Law 104-106. This standard shall be used in designing and implementing cryptographic modules that Federal departments and agencies operate or are operated for them under contract. See https://nvlpubs.nist.gov/nistpubs/FIPS/NIST.FIPS.140-2.pdf To meet this, the system has to have cryptographic software provided by a vendor that has undergone this certification. This means providing documentation, test results, design information, and independent third party review by an accredited lab. While open source software is capable of meeting this, it does not meet FIPS-140 unless the vendor submits to this process.


var_system_crypto_policy='FIPS'


stderr_of_call=$(update-crypto-policies --set ${var_system_crypto_policy} 2>&1 > /dev/null)
rc=$?

if test "$rc" = 127; then
	echo "$stderr_of_call" >&2
	echo "Make sure that the script is installed on the remediated system." >&2
	echo "See output of the 'dnf provides update-crypto-policies' command" >&2
	echo "to see what package to (re)install" >&2

	false  # end with an error code
elif test "$rc" != 0; then
	echo "Error invoking the update-crypto-policies script: $stderr_of_call" >&2
	false  # end with an error code
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: XCCDF Value var_system_crypto_policy # promote to variable
  set_fact:
    var_system_crypto_policy: !!str FIPS
  tags:
    - always

- name: Configure System Cryptography Policy
  lineinfile:
    path: /etc/crypto-policies/config
    regexp: ^(?!#)(\S+)$
    line: '{{ var_system_crypto_policy }}'
    create: true
  tags:
    - NIST-800-53-AC-17(2)
    - NIST-800-53-AC-17(a)
    - NIST-800-53-CM-6(a)
    - NIST-800-53-MA-4(6)
    - NIST-800-53-SC-12(2)
    - NIST-800-53-SC-12(3)
    - NIST-800-53-SC-13
    - configure_crypto_policy
    - high_severity
    - low_complexity
    - low_disruption
    - no_reboot_needed
    - restrict_strategy

- name: Verify that Crypto Policy is Set (runtime)
  command: /usr/bin/update-crypto-policies --set {{ var_system_crypto_policy }}
  tags:
    - NIST-800-53-AC-17(2)
    - NIST-800-53-AC-17(a)
    - NIST-800-53-CM-6(a)
    - NIST-800-53-MA-4(6)
    - NIST-800-53-SC-12(2)
    - NIST-800-53-SC-12(3)
    - NIST-800-53-SC-13
    - configure_crypto_policy
    - high_severity
    - low_complexity
    - low_disruption
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

check for crypto policy correctly configured in /etc/crypto-policies/config  oval:ssg-test_configure_crypto_policy:tst:1  false

Following items have been found on the system:
PathContent
/etc/crypto-policies/configDEFAULT

check for crypto policy correctly configured in /etc/crypto-policies/state/current  oval:ssg-test_configure_crypto_policy_current:tst:1  false

Following items have been found on the system:
PathContent
/etc/crypto-policies/state/currentDEFAULT

Check if update-crypto-policies has been run  oval:ssg-test_crypto_policies_updated:tst:1  true

Following items have been found on the system:
Var refValue
oval:ssg-variable_crypto_policies_config_file_timestamp:var:11735487419

Check if /etc/crypto-policies/back-ends/nss.config exists  oval:ssg-test_crypto_policy_nss_config:tst:1  true

Following items have been found on the system:
PathTypeUIDGIDSize (B)Permissions
/etc/crypto-policies/back-ends/nss.configregular00447rw-r--r-- 
Configure Kerberos to use System Crypto Policyxccdf_org.ssgproject.content_rule_configure_kerberos_crypto_policy high

Configure Kerberos to use System Crypto Policy

Rule IDxccdf_org.ssgproject.content_rule_configure_kerberos_crypto_policy
Result
pass
Multi-check ruleno
OVAL Definition IDoval:ssg-configure_kerberos_crypto_policy:def:1
Time2024-12-29T17:33:54+01:00
Severityhigh
Identifiers and References

References:  0418, 1055, 1402, CIP-003-8 R4.2, CIP-007-3 R5.1, SC-13, SC-12(2), SC-12(3), SRG-OS-000120-GPOS-00061

Description
Crypto Policies provide a centralized control over crypto algorithms usage of many packages. Kerberos is supported by crypto policy, but it's configuration may be set up to ignore it. To check that Crypto Policies settings for Kerberos are configured correctly, examine that there is a symlink at /etc/krb5.conf.d/crypto-policies targeting /etc/cypto-policies/back-ends/krb5.config. If the symlink exists, kerberos is configured to use the system-wide crypto policy settings.
Rationale
Overriding the system crypto policy makes the behavior of Kerberos violate expectations, and makes system configuration more fragmented.
OVAL test results details

Check if kerberos configuration symlink and crypto policy kerberos backend symlink point to same file  oval:ssg-test_configure_kerberos_crypto_policy_symlink:tst:1  true

Following items have been found on the system:
Var refValue
oval:ssg-var_symlink_kerberos_crypto_policy_configuration:var:1/usr/share/crypto-policies/DEFAULT/krb5.txt

Check if kerberos configuration symlink links to the crypto-policy backend file  oval:ssg-test_configure_kerberos_crypto_policy_nosymlink:tst:1  false

Following items have been found on the system:
Var refValue
oval:ssg-var_symlink_kerberos_crypto_policy_configuration:var:1/usr/share/crypto-policies/DEFAULT/krb5.txt
Configure Libreswan to use System Crypto Policyxccdf_org.ssgproject.content_rule_configure_libreswan_crypto_policy high

Configure Libreswan to use System Crypto Policy

Rule IDxccdf_org.ssgproject.content_rule_configure_libreswan_crypto_policy
Result
pass
Multi-check ruleno
OVAL Definition IDoval:ssg-configure_libreswan_crypto_policy:def:1
Time2024-12-29T17:33:54+01:00
Severityhigh
Identifiers and References

References:  CIP-003-8 R4.2, CIP-007-3 R5.1, CM-6(a), MA-4(6), SC-13, SC-12(2), SC-12(3), FCS_IPSEC_EXT.1.4, FCS_IPSEC_EXT.1.6, SRG-OS-000033-GPOS-00014

Description
Crypto Policies provide a centralized control over crypto algorithms usage of many packages. Libreswan is supported by system crypto policy, but the Libreswan configuration may be set up to ignore it. To check that Crypto Policies settings are configured correctly, ensure that the /etc/ipsec.conf includes the appropriate configuration file. In /etc/ipsec.conf, make sure that the following line is not commented out or superseded by later includes: include /etc/crypto-policies/back-ends/libreswan.config
Rationale
Overriding the system crypto policy makes the behavior of the Libreswan service violate expectations, and makes system configuration more fragmented.
OVAL test results details

package libreswan is installed  oval:ssg-test_package_libreswan_installed:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_test_package_libreswan_installed:obj:1 of type rpminfo_object
Name
libreswan

Check that the libreswan configuration includes the crypto policy config file  oval:ssg-test_configure_libreswan_crypto_policy:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_configure_libreswan_crypto_policy:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/ipsec.conf^\s*include\s+/etc/crypto-policies/back-ends/libreswan.config\s*(?:#.*)?$1
Configure OpenSSL library to use System Crypto Policyxccdf_org.ssgproject.content_rule_configure_openssl_crypto_policy medium

Configure OpenSSL library to use System Crypto Policy

Rule IDxccdf_org.ssgproject.content_rule_configure_openssl_crypto_policy
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-configure_openssl_crypto_policy:def:1
Time2024-12-29T17:33:54+01:00
Severitymedium
Identifiers and References

References:  CCI-001453, CIP-003-8 R4.2, CIP-007-3 R5.1, CIP-007-3 R7.1, AC-17(a), AC-17(2), CM-6(a), MA-4(6), SC-13, SC-12(2), SC-12(3), SRG-OS-000250-GPOS-00093

Description
Crypto Policies provide a centralized control over crypto algorithms usage of many packages. OpenSSL is supported by crypto policy, but the OpenSSL configuration may be set up to ignore it. To check that Crypto Policies settings are configured correctly, you have to examine the OpenSSL config file available under /etc/pki/tls/openssl.cnf. This file has the ini format, and it enables crypto policy support if there is a [ crypto_policy ] section that contains the .include /etc/crypto-policies/back-ends/opensslcnf.config directive.
Rationale
Overriding the system crypto policy makes the behavior of the Java runtime violates expectations, and makes system configuration more fragmented.


OPENSSL_CRYPTO_POLICY_SECTION='[ crypto_policy ]'
OPENSSL_CRYPTO_POLICY_SECTION_REGEX='\[\s*crypto_policy\s*\]'
OPENSSL_CRYPTO_POLICY_INCLUSION='.include /etc/crypto-policies/back-ends/opensslcnf.config'
OPENSSL_CRYPTO_POLICY_INCLUSION_REGEX='^\s*\.include\s*/etc/crypto-policies/back-ends/opensslcnf.config$'

function remediate_openssl_crypto_policy() {
	CONFIG_FILE="/etc/pki/tls/openssl.cnf"
	if test -f "$CONFIG_FILE"; then
		if ! grep -q "^\\s*$OPENSSL_CRYPTO_POLICY_SECTION_REGEX" "$CONFIG_FILE"; then
			printf '\n%s\n\n%s' "$OPENSSL_CRYPTO_POLICY_SECTION" "$OPENSSL_CRYPTO_POLICY_INCLUSION" >> "$CONFIG_FILE"
			return 0
		elif ! grep -q "^\\s*$OPENSSL_CRYPTO_POLICY_INCLUSION_REGEX" "$CONFIG_FILE"; then
			sed -i "s|$OPENSSL_CRYPTO_POLICY_SECTION_REGEX|&\\n\\n$OPENSSL_CRYPTO_POLICY_INCLUSION\\n|" "$CONFIG_FILE"
			return 0
		fi
	else
		echo "Aborting remediation as '$CONFIG_FILE' was not even found." >&2
		return 1
	fi
}

remediate_openssl_crypto_policy

Complexity:low
Disruption:medium
- name: Test for crypto_policy group
  command: grep '^\s*\[\s*crypto_policy\s*]' /etc/pki/tls/openssl.cnf
  register: test_crypto_policy_group
  ignore_errors: true
  changed_when: false
  check_mode: false
  tags:
    - NIST-800-53-AC-17(2)
    - NIST-800-53-AC-17(a)
    - NIST-800-53-CM-6(a)
    - NIST-800-53-MA-4(6)
    - NIST-800-53-SC-12(2)
    - NIST-800-53-SC-12(3)
    - NIST-800-53-SC-13
    - configure_openssl_crypto_policy
    - low_complexity
    - medium_disruption
    - medium_severity
    - no_reboot_needed
    - unknown_strategy

- name: Add .include for opensslcnf.config to crypto_policy section
  lineinfile:
    create: true
    insertafter: ^\s*\[\s*crypto_policy\s*]\s*
    line: .include /etc/crypto-policies/back-ends/opensslcnf.config
    path: /etc/pki/tls/openssl.cnf
  when:
    - test_crypto_policy_group.stdout is defined
    - test_crypto_policy_group.stdout | length > 0
  tags:
    - NIST-800-53-AC-17(2)
    - NIST-800-53-AC-17(a)
    - NIST-800-53-CM-6(a)
    - NIST-800-53-MA-4(6)
    - NIST-800-53-SC-12(2)
    - NIST-800-53-SC-12(3)
    - NIST-800-53-SC-13
    - configure_openssl_crypto_policy
    - low_complexity
    - medium_disruption
    - medium_severity
    - no_reboot_needed
    - unknown_strategy

- name: Add crypto_policy group and set include opensslcnf.config
  lineinfile:
    create: true
    line: |-
      [crypto_policy]
      .include /etc/crypto-policies/back-ends/opensslcnf.config
    path: /etc/pki/tls/openssl.cnf
  when:
    - test_crypto_policy_group.stdout is defined
    - test_crypto_policy_group.stdout | length < 1
  tags:
    - NIST-800-53-AC-17(2)
    - NIST-800-53-AC-17(a)
    - NIST-800-53-CM-6(a)
    - NIST-800-53-MA-4(6)
    - NIST-800-53-SC-12(2)
    - NIST-800-53-SC-12(3)
    - NIST-800-53-SC-13
    - configure_openssl_crypto_policy
    - low_complexity
    - medium_disruption
    - medium_severity
    - no_reboot_needed
    - unknown_strategy
OVAL test results details

Check that the configuration mandates usage of system-wide crypto policies.  oval:ssg-test_configure_openssl_crypto_policy:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_configure_openssl_crypto_policy:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/pki/tls/openssl.cnf^\s*\[\s*crypto_policy\s*\]\s*\n*\s*\.include\s*/etc/crypto-policies/back-ends/opensslcnf.config\s*$1
Configure SSH to use System Crypto Policyxccdf_org.ssgproject.content_rule_configure_ssh_crypto_policy medium

Configure SSH to use System Crypto Policy

Rule IDxccdf_org.ssgproject.content_rule_configure_ssh_crypto_policy
Result
pass
Multi-check ruleno
OVAL Definition IDoval:ssg-configure_ssh_crypto_policy:def:1
Time2024-12-29T17:33:54+01:00
Severitymedium
Identifiers and References

References:  164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.312(e)(1), 164.312(e)(2)(ii), CIP-003-8 R4.2, CIP-007-3 R5.1, CIP-007-3 R7.1, AC-17(a), AC-17(2), CM-6(a), MA-4(6), SC-13, SRG-OS-000250-GPOS-00093

Description
Crypto Policies provide a centralized control over crypto algorithms usage of many packages. SSH is supported by crypto policy, but the SSH configuration may be set up to ignore it. To check that Crypto Policies settings are configured correctly, ensure that the CRYPTO_POLICY variable is either commented or not set at all in the /etc/sysconfig/sshd.
Rationale
Overriding the system crypto policy makes the behavior of the SSH service violate expectations, and makes system configuration more fragmented.
OVAL test results details

Check that the SSH configuration mandates usage of system-wide crypto policies.  oval:ssg-test_configure_ssh_crypto_policy:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-object_configure_ssh_crypto_policy:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/sysconfig/sshd^\s*CRYPTO_POLICY\s*=.*$1
The Installed Operating System Is Vendor Supportedxccdf_org.ssgproject.content_rule_installed_OS_is_vendor_supported high

The Installed Operating System Is Vendor Supported

Rule IDxccdf_org.ssgproject.content_rule_installed_OS_is_vendor_supported
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-installed_OS_is_vendor_supported:def:1
Time2024-12-29T17:33:54+01:00
Severityhigh
Identifiers and References

References:  18, 20, 4, APO12.01, APO12.02, APO12.03, APO12.04, BAI03.10, DSS05.01, DSS05.02, CCI-000366, 4.2.3, 4.2.3.12, 4.2.3.7, 4.2.3.9, A.12.6.1, A.14.2.3, A.16.1.3, A.18.2.2, A.18.2.3, CM-6(a), MA-6, SA-13(a), ID.RA-1, PR.IP-12, SRG-OS-000480-GPOS-00227

Description
The installed operating system must be maintained by a vendor. Red Hat Enterprise Linux is supported by Red Hat, Inc. As the Red Hat Enterprise Linux vendor, Red Hat, Inc. is responsible for providing security patches.
Rationale
An operating system is considered "supported" if the vendor continues to provide security patches for the product. With an unsupported release, it will not be possible to resolve any security issue discovered in the system software.
Warnings
warning  There is no remediation besides switching to a different operating system.
OVAL test results details

installed OS part of unix family  oval:ssg-test_rhel7_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

installed OS part of unix family  oval:ssg-test_rhel7_unix_family:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhel7_unix_family:obj:1 of type family_object

redhat-release-client is version 7  oval:ssg-test_rhel7_client:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhel7_client:obj:1 of type rpminfo_object
Name
redhat-release-client

redhat-release-client is version 7  oval:ssg-test_rhel7_client:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhel7_client:obj:1 of type rpminfo_object
Name
redhat-release-client

redhat-release-workstation is version 7  oval:ssg-test_rhel7_workstation:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhel7_workstation:obj:1 of type rpminfo_object
Name
redhat-release-workstation

redhat-release-workstation is version 7  oval:ssg-test_rhel7_workstation:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhel7_workstation:obj:1 of type rpminfo_object
Name
redhat-release-workstation

redhat-release-server is version 7  oval:ssg-test_rhel7_server:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhel7_server:obj:1 of type rpminfo_object
Name
redhat-release-server

redhat-release-server is version 7  oval:ssg-test_rhel7_server:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhel7_server:obj:1 of type rpminfo_object
Name
redhat-release-server

redhat-release-computenode is version 7  oval:ssg-test_rhel7_computenode:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhel7_computenode:obj:1 of type rpminfo_object
Name
redhat-release-computenode

redhat-release-computenode is version 7  oval:ssg-test_rhel7_computenode:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhel7_computenode:obj:1 of type rpminfo_object
Name
redhat-release-computenode

redhat-release-virtualization-host RPM package is installed  oval:ssg-test_rhvh4_version:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhvh4_version:obj:1 of type rpminfo_object
Name
redhat-release-virtualization-host

redhat-release-virtualization-host RPM package is installed  oval:ssg-test_rhvh4_version:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhvh4_version:obj:1 of type rpminfo_object
Name
redhat-release-virtualization-host

RHEVH base RHEL is version 7  oval:ssg-test_rhevh_rhel7_version:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhevh_rhel7_version:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/redhat-release^Red Hat Enterprise Linux release (\d)\.\d+$1

RHEVH base RHEL is version 7  oval:ssg-test_rhevh_rhel7_version:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhevh_rhel7_version:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/redhat-release^Red Hat Enterprise Linux release (\d)\.\d+$1

installed OS part of unix family  oval:ssg-test_rhel7_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

installed OS part of unix family  oval:ssg-test_rhel7_unix_family:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhel7_unix_family:obj:1 of type family_object

redhat-release-client is version 7  oval:ssg-test_rhel7_client:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhel7_client:obj:1 of type rpminfo_object
Name
redhat-release-client

redhat-release-client is version 7  oval:ssg-test_rhel7_client:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhel7_client:obj:1 of type rpminfo_object
Name
redhat-release-client

redhat-release-workstation is version 7  oval:ssg-test_rhel7_workstation:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhel7_workstation:obj:1 of type rpminfo_object
Name
redhat-release-workstation

redhat-release-workstation is version 7  oval:ssg-test_rhel7_workstation:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhel7_workstation:obj:1 of type rpminfo_object
Name
redhat-release-workstation

redhat-release-server is version 7  oval:ssg-test_rhel7_server:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhel7_server:obj:1 of type rpminfo_object
Name
redhat-release-server

redhat-release-server is version 7  oval:ssg-test_rhel7_server:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhel7_server:obj:1 of type rpminfo_object
Name
redhat-release-server

redhat-release-computenode is version 7  oval:ssg-test_rhel7_computenode:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhel7_computenode:obj:1 of type rpminfo_object
Name
redhat-release-computenode

redhat-release-computenode is version 7  oval:ssg-test_rhel7_computenode:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhel7_computenode:obj:1 of type rpminfo_object
Name
redhat-release-computenode

redhat-release-virtualization-host RPM package is installed  oval:ssg-test_rhvh4_version:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhvh4_version:obj:1 of type rpminfo_object
Name
redhat-release-virtualization-host

redhat-release-virtualization-host RPM package is installed  oval:ssg-test_rhvh4_version:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhvh4_version:obj:1 of type rpminfo_object
Name
redhat-release-virtualization-host

RHEVH base RHEL is version 7  oval:ssg-test_rhevh_rhel7_version:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhevh_rhel7_version:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/redhat-release^Red Hat Enterprise Linux release (\d)\.\d+$1

RHEVH base RHEL is version 7  oval:ssg-test_rhevh_rhel7_version:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhevh_rhel7_version:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/redhat-release^Red Hat Enterprise Linux release (\d)\.\d+$1

installed OS part of unix family  oval:ssg-test_rhel8_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

installed OS part of unix family  oval:ssg-test_rhel8_unix_family:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhel8_unix_family:obj:1 of type family_object

redhat-release is version 8  oval:ssg-test_rhel8:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhel8:obj:1 of type rpminfo_object
Name
redhat-release

redhat-release is version 8  oval:ssg-test_rhel8:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhel8:obj:1 of type rpminfo_object
Name
redhat-release

redhat-release-virtualization-host RPM package is installed  oval:ssg-test_rhvh4_version:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhvh4_version:obj:1 of type rpminfo_object
Name
redhat-release-virtualization-host

redhat-release-virtualization-host RPM package is installed  oval:ssg-test_rhvh4_version:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhvh4_version:obj:1 of type rpminfo_object
Name
redhat-release-virtualization-host

RHEVH base RHEL is version 8  oval:ssg-test_rhevh_rhel8_version:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhevh_rhel8_version:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/redhat-release^Red Hat Enterprise Linux release (\d)\.\d+$1

RHEVH base RHEL is version 8  oval:ssg-test_rhevh_rhel8_version:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhevh_rhel8_version:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/redhat-release^Red Hat Enterprise Linux release (\d)\.\d+$1

installed OS part of unix family  oval:ssg-test_rhel8_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

installed OS part of unix family  oval:ssg-test_rhel8_unix_family:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhel8_unix_family:obj:1 of type family_object

redhat-release is version 8  oval:ssg-test_rhel8:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhel8:obj:1 of type rpminfo_object
Name
redhat-release

redhat-release is version 8  oval:ssg-test_rhel8:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhel8:obj:1 of type rpminfo_object
Name
redhat-release

redhat-release-virtualization-host RPM package is installed  oval:ssg-test_rhvh4_version:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhvh4_version:obj:1 of type rpminfo_object
Name
redhat-release-virtualization-host

redhat-release-virtualization-host RPM package is installed  oval:ssg-test_rhvh4_version:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhvh4_version:obj:1 of type rpminfo_object
Name
redhat-release-virtualization-host

RHEVH base RHEL is version 8  oval:ssg-test_rhevh_rhel8_version:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhevh_rhel8_version:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/redhat-release^Red Hat Enterprise Linux release (\d)\.\d+$1

RHEVH base RHEL is version 8  oval:ssg-test_rhevh_rhel8_version:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhevh_rhel8_version:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/redhat-release^Red Hat Enterprise Linux release (\d)\.\d+$1

installed OS part of unix family  oval:ssg-test_rhel9_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

installed OS part of unix family  oval:ssg-test_rhel9_unix_family:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhel9_unix_family:obj:1 of type family_object

redhat-release is version 9  oval:ssg-test_rhel9:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhel9:obj:1 of type rpminfo_object
Name
redhat-release

redhat-release is version 9  oval:ssg-test_rhel9:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhel9:obj:1 of type rpminfo_object
Name
redhat-release

redhat-release-virtualization-host RPM package is installed  oval:ssg-test_rhvh4_version:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhvh4_version:obj:1 of type rpminfo_object
Name
redhat-release-virtualization-host

redhat-release-virtualization-host RPM package is installed  oval:ssg-test_rhvh4_version:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhvh4_version:obj:1 of type rpminfo_object
Name
redhat-release-virtualization-host

RHEVH base RHEL is version 9  oval:ssg-test_rhevh_rhel9_version:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhevh_rhel9_version:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/redhat-release^Red Hat Enterprise Linux release (\d)\.\d+$1

RHEVH base RHEL is version 9  oval:ssg-test_rhevh_rhel9_version:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhevh_rhel9_version:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/redhat-release^Red Hat Enterprise Linux release (\d)\.\d+$1

installed OS part of unix family  oval:ssg-test_rhel9_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

installed OS part of unix family  oval:ssg-test_rhel9_unix_family:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhel9_unix_family:obj:1 of type family_object

redhat-release is version 9  oval:ssg-test_rhel9:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhel9:obj:1 of type rpminfo_object
Name
redhat-release

redhat-release is version 9  oval:ssg-test_rhel9:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhel9:obj:1 of type rpminfo_object
Name
redhat-release

redhat-release-virtualization-host RPM package is installed  oval:ssg-test_rhvh4_version:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhvh4_version:obj:1 of type rpminfo_object
Name
redhat-release-virtualization-host

redhat-release-virtualization-host RPM package is installed  oval:ssg-test_rhvh4_version:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhvh4_version:obj:1 of type rpminfo_object
Name
redhat-release-virtualization-host

RHEVH base RHEL is version 9  oval:ssg-test_rhevh_rhel9_version:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhevh_rhel9_version:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/redhat-release^Red Hat Enterprise Linux release (\d)\.\d+$1

RHEVH base RHEL is version 9  oval:ssg-test_rhevh_rhel9_version:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_rhevh_rhel9_version:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/redhat-release^Red Hat Enterprise Linux release (\d)\.\d+$1

Test installed OS is part of the unix family  oval:ssg-test_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

Test installed OS is part of the unix family  oval:ssg-test_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

Test installed OS is part of the unix family  oval:ssg-test_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

Test installed OS is part of the unix family  oval:ssg-test_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

oraclelinux-release is version 7  oval:ssg-test_ol7_system:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_ol7_system:obj:1 of type rpminfo_object
Name
oraclelinux-release

oraclelinux-release is version 7  oval:ssg-test_ol7_system:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_ol7_system:obj:1 of type rpminfo_object
Name
oraclelinux-release

Test installed OS is part of the unix family  oval:ssg-test_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

Test installed OS is part of the unix family  oval:ssg-test_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

Test installed OS is part of the unix family  oval:ssg-test_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

Test installed OS is part of the unix family  oval:ssg-test_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

oraclelinux-release is version 7  oval:ssg-test_ol7_system:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_ol7_system:obj:1 of type rpminfo_object
Name
oraclelinux-release

oraclelinux-release is version 7  oval:ssg-test_ol7_system:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_ol7_system:obj:1 of type rpminfo_object
Name
oraclelinux-release

Test installed OS is part of the unix family  oval:ssg-test_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

Test installed OS is part of the unix family  oval:ssg-test_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

Test installed OS is part of the unix family  oval:ssg-test_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

Test installed OS is part of the unix family  oval:ssg-test_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

oraclelinux-release is version 8  oval:ssg-test_ol8_system:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_ol8_system:obj:1 of type rpminfo_object
Name
oraclelinux-release

oraclelinux-release is version 8  oval:ssg-test_ol8_system:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_ol8_system:obj:1 of type rpminfo_object
Name
oraclelinux-release

Test installed OS is part of the unix family  oval:ssg-test_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

Test installed OS is part of the unix family  oval:ssg-test_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

Test installed OS is part of the unix family  oval:ssg-test_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

Test installed OS is part of the unix family  oval:ssg-test_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

oraclelinux-release is version 8  oval:ssg-test_ol8_system:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_ol8_system:obj:1 of type rpminfo_object
Name
oraclelinux-release

oraclelinux-release is version 8  oval:ssg-test_ol8_system:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_ol8_system:obj:1 of type rpminfo_object
Name
oraclelinux-release

installed OS part of unix family  oval:ssg-test_sle12_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

installed OS part of unix family  oval:ssg-test_sle12_unix_family:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_sle12_unix_family:obj:1 of type family_object

sled-release is version 6  oval:ssg-test_sle12_desktop:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_sle12_desktop:obj:1 of type rpminfo_object
Name
sled-release

sled-release is version 6  oval:ssg-test_sle12_desktop:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_sle12_desktop:obj:1 of type rpminfo_object
Name
sled-release

sles-release is version 6  oval:ssg-test_sle12_server:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_sle12_server:obj:1 of type rpminfo_object
Name
sles-release

sles-release is version 6  oval:ssg-test_sle12_server:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_sle12_server:obj:1 of type rpminfo_object
Name
sles-release

SLES_SAP-release is version 12  oval:ssg-test_sles_12_for_sap:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_sles_12_for_sap:obj:1 of type rpminfo_object
Name
SLES_SAP-release

SLES_SAP-release is version 12  oval:ssg-test_sles_12_for_sap:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_sles_12_for_sap:obj:1 of type rpminfo_object
Name
SLES_SAP-release

installed OS part of unix family  oval:ssg-test_sle12_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

installed OS part of unix family  oval:ssg-test_sle12_unix_family:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_sle12_unix_family:obj:1 of type family_object

sled-release is version 6  oval:ssg-test_sle12_desktop:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_sle12_desktop:obj:1 of type rpminfo_object
Name
sled-release

sled-release is version 6  oval:ssg-test_sle12_desktop:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_sle12_desktop:obj:1 of type rpminfo_object
Name
sled-release

sles-release is version 6  oval:ssg-test_sle12_server:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_sle12_server:obj:1 of type rpminfo_object
Name
sles-release

sles-release is version 6  oval:ssg-test_sle12_server:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_sle12_server:obj:1 of type rpminfo_object
Name
sles-release

SLES_SAP-release is version 12  oval:ssg-test_sles_12_for_sap:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_sles_12_for_sap:obj:1 of type rpminfo_object
Name
SLES_SAP-release

SLES_SAP-release is version 12  oval:ssg-test_sles_12_for_sap:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_sles_12_for_sap:obj:1 of type rpminfo_object
Name
SLES_SAP-release

installed OS part of unix family  oval:ssg-test_sle15_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

installed OS part of unix family  oval:ssg-test_sle15_unix_family:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_sle15_unix_family:obj:1 of type family_object

sled-release is version 15  oval:ssg-test_sle15_desktop:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_sle15_desktop:obj:1 of type rpminfo_object
Name
sled-release

sled-release is version 15  oval:ssg-test_sle15_desktop:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_sle15_desktop:obj:1 of type rpminfo_object
Name
sled-release

sles-release is version 15  oval:ssg-test_sle15_server:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_sle15_server:obj:1 of type rpminfo_object
Name
sles-release

sles-release is version 15  oval:ssg-test_sle15_server:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_sle15_server:obj:1 of type rpminfo_object
Name
sles-release

SLES_SAP-release is version 15  oval:ssg-test_sles_15_for_sap:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_sles_15_for_sap:obj:1 of type rpminfo_object
Name
SLES_SAP-release

SLES_SAP-release is version 15  oval:ssg-test_sles_15_for_sap:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_sles_15_for_sap:obj:1 of type rpminfo_object
Name
SLES_SAP-release

installed OS part of unix family  oval:ssg-test_sle15_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

installed OS part of unix family  oval:ssg-test_sle15_unix_family:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_sle15_unix_family:obj:1 of type family_object

sled-release is version 15  oval:ssg-test_sle15_desktop:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_sle15_desktop:obj:1 of type rpminfo_object
Name
sled-release

sled-release is version 15  oval:ssg-test_sle15_desktop:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_sle15_desktop:obj:1 of type rpminfo_object
Name
sled-release

sles-release is version 15  oval:ssg-test_sle15_server:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_sle15_server:obj:1 of type rpminfo_object
Name
sles-release

sles-release is version 15  oval:ssg-test_sle15_server:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_sle15_server:obj:1 of type rpminfo_object
Name
sles-release

SLES_SAP-release is version 15  oval:ssg-test_sles_15_for_sap:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_sles_15_for_sap:obj:1 of type rpminfo_object
Name
SLES_SAP-release

SLES_SAP-release is version 15  oval:ssg-test_sles_15_for_sap:tst:1  not evaluated

No items have been found conforming to the following objects:
Object oval:ssg-obj_sles_15_for_sap:obj:1 of type rpminfo_object
Name
SLES_SAP-release
Enable GNOME3 Screensaver Idle Activationxccdf_org.ssgproject.content_rule_dconf_gnome_screensaver_idle_activation_enabled medium

Enable GNOME3 Screensaver Idle Activation

Rule IDxccdf_org.ssgproject.content_rule_dconf_gnome_screensaver_idle_activation_enabled
Result
notapplicable
Multi-check ruleno
Time2024-12-29T17:33:54+01:00
Severitymedium
Identifiers and References

References:  1, 12, 15, 16, 5.5.5, DSS05.04, DSS05.10, DSS06.10, 3.1.10, CCI-000057, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, SR 1.1, SR 1.10, SR 1.2, SR 1.5, SR 1.7, SR 1.8, SR 1.9, A.18.1.4, A.9.2.1, A.9.2.4, A.9.3.1, A.9.4.2, A.9.4.3, CM-6(a), AC-11(a), PR.AC-7, FMT_MOF_EXT.1, Req-8.1.8, SRG-OS-000029-GPOS-00010

Description
To activate the screensaver in the GNOME3 desktop after a period of inactivity, add or set idle-activation-enabled to true in /etc/dconf/db/local.d/00-security-settings. For example:
[org/gnome/desktop/screensaver]
idle-activation-enabled=true
Once the setting has been added, add a lock to /etc/dconf/db/local.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/desktop/screensaver/idle-activation-enabled
After the settings have been set, run dconf update.
Rationale
A session time-out lock is a temporary action taken when a user stops work and moves away from the immediate physical vicinity of the information system but does not logout because of the temporary nature of the absence. Rather than relying on the user to manually lock their operating system session prior to vacating the vicinity, GNOME desktops can be configured to identify when a user's session has idled and take action to initiate the session lock.

Enabling idle activation of the screensaver ensures the screensaver will be activated after the idle delay. Applications requiring continuous, real-time screen display (such as network management products) require the login session does not have administrator rights and the display station is located in a controlled-access area.
Set GNOME3 Screensaver Inactivity Timeoutxccdf_org.ssgproject.content_rule_dconf_gnome_screensaver_idle_delay medium

Set GNOME3 Screensaver Inactivity Timeout

Rule IDxccdf_org.ssgproject.content_rule_dconf_gnome_screensaver_idle_delay
Result
notapplicable
Multi-check ruleno
Time2024-12-29T17:33:54+01:00
Severitymedium
Identifiers and References

References:  1, 12, 15, 16, 5.5.5, DSS05.04, DSS05.10, DSS06.10, 3.1.10, CCI-000057, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, SR 1.1, SR 1.10, SR 1.2, SR 1.5, SR 1.7, SR 1.8, SR 1.9, A.18.1.4, A.9.2.1, A.9.2.4, A.9.3.1, A.9.4.2, A.9.4.3, AC-11(a), CM-6(a), PR.AC-7, FMT_MOF_EXT.1, Req-8.1.8, SRG-OS-000029-GPOS-00010

Description
The idle time-out value for inactivity in the GNOME3 desktop is configured via the idle-delay setting must be set under an appropriate configuration file(s) in the /etc/dconf/db/local.d directory and locked in /etc/dconf/db/local.d/locks directory to prevent user modification.

For example, to configure the system for a 15 minute delay, add the following to /etc/dconf/db/local.d/00-security-settings:
[org/gnome/desktop/session]
idle-delay=uint32 900
Once the setting has been added, add a lock to /etc/dconf/db/local.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/desktop/session/idle-delay
After the settings have been set, run dconf update.
Rationale
A session time-out lock is a temporary action taken when a user stops work and moves away from the immediate physical vicinity of the information system but does not logout because of the temporary nature of the absence. Rather than relying on the user to manually lock their operating system session prior to vacating the vicinity, GNOME3 can be configured to identify when a user's session has idled and take action to initiate a session lock.
Set GNOME3 Screensaver Lock Delay After Activation Periodxccdf_org.ssgproject.content_rule_dconf_gnome_screensaver_lock_delay medium

Set GNOME3 Screensaver Lock Delay After Activation Period

Rule IDxccdf_org.ssgproject.content_rule_dconf_gnome_screensaver_lock_delay
Result
notapplicable
Multi-check ruleno
Time2024-12-29T17:33:54+01:00
Severitymedium
Identifiers and References

References:  1, 12, 15, 16, DSS05.04, DSS05.10, DSS06.10, 3.1.10, CCI-000056, CCI-000057, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, SR 1.1, SR 1.10, SR 1.2, SR 1.5, SR 1.7, SR 1.8, SR 1.9, A.18.1.4, A.9.2.1, A.9.2.4, A.9.3.1, A.9.4.2, A.9.4.3, AC-11(a), CM-6(a), PR.AC-7, FMT_MOF_EXT.1, Req-8.1.8, SRG-OS-000029-GPOS-00010

Description
To activate the locking delay of the screensaver in the GNOME3 desktop when the screensaver is activated, add or set lock-delay to uint32 0 in /etc/dconf/db/local.d/00-security-settings. For example:
[org/gnome/desktop/screensaver]
lock-delay=uint32 0
Once the setting has been added, add a lock to /etc/dconf/db/local.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/desktop/screensaver/lock-delay
After the settings have been set, run dconf update.
Rationale
A session lock is a temporary action taken when a user stops work and moves away from the immediate physical vicinity of the information system but does not want to logout because of the temporary nature of the absense.
Enable GNOME3 Screensaver Lock After Idle Periodxccdf_org.ssgproject.content_rule_dconf_gnome_screensaver_lock_enabled medium

Enable GNOME3 Screensaver Lock After Idle Period

Rule IDxccdf_org.ssgproject.content_rule_dconf_gnome_screensaver_lock_enabled
Result
notapplicable
Multi-check ruleno
Time2024-12-29T17:33:54+01:00
Severitymedium
Identifiers and References

References:  1, 12, 15, 16, 5.5.5, DSS05.04, DSS05.10, DSS06.10, 3.1.10, CCI-000056, CCI-000058, CCI-000060, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, SR 1.1, SR 1.10, SR 1.2, SR 1.5, SR 1.7, SR 1.8, SR 1.9, A.18.1.4, A.9.2.1, A.9.2.4, A.9.3.1, A.9.4.2, A.9.4.3, CM-6(a), PR.AC-7, FMT_MOF_EXT.1, Req-8.1.8, SRG-OS-000028-GPOS-00009, SRG-OS-000030-GPOS-00011

Description
To activate locking of the screensaver in the GNOME3 desktop when it is activated, add or set lock-enabled to true in /etc/dconf/db/local.d/00-security-settings. For example:
[org/gnome/desktop/screensaver]
lock-enabled=true
Once the settings have been added, add a lock to /etc/dconf/db/local.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/desktop/screensaver/lock-enabled
After the settings have been set, run dconf update.
Rationale
A session lock is a temporary action taken when a user stops work and moves away from the immediate physical vicinity of the information system but does not want to logout because of the temporary nature of the absense.
Implement Blank Screensaverxccdf_org.ssgproject.content_rule_dconf_gnome_screensaver_mode_blank medium

Implement Blank Screensaver

Rule IDxccdf_org.ssgproject.content_rule_dconf_gnome_screensaver_mode_blank
Result
notapplicable
Multi-check ruleno
Time2024-12-29T17:33:54+01:00
Severitymedium
Identifiers and References

References:  1, 12, 15, 16, 5.5.5, DSS05.04, DSS05.10, DSS06.10, 3.1.10, CCI-000060, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, SR 1.1, SR 1.10, SR 1.2, SR 1.5, SR 1.7, SR 1.8, SR 1.9, A.18.1.4, A.9.2.1, A.9.2.4, A.9.3.1, A.9.4.2, A.9.4.3, AC-11(1), CM-6(a), AC-11(1).1, PR.AC-7, FMT_MOF_EXT.1, Req-8.1.8, SRG-OS-000031-GPOS-00012

Description
To set the screensaver mode in the GNOME3 desktop to a blank screen, add or set picture-uri to string '' in /etc/dconf/db/local.d/00-security-settings. For example:
[org/gnome/desktop/screensaver]
picture-uri=''
Once the settings have been added, add a lock to /etc/dconf/db/local.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/desktop/screensaver/picture-uri
After the settings have been set, run dconf update.
Rationale
Setting the screensaver mode to blank-only conceals the contents of the display from passersby.
Ensure Users Cannot Change GNOME3 Screensaver Settingsxccdf_org.ssgproject.content_rule_dconf_gnome_screensaver_user_locks medium

Ensure Users Cannot Change GNOME3 Screensaver Settings

Rule IDxccdf_org.ssgproject.content_rule_dconf_gnome_screensaver_user_locks
Result
notapplicable
Multi-check ruleno
Time2024-12-29T17:33:54+01:00
Severitymedium
Identifiers and References

References:  1, 12, 15, 16, DSS05.04, DSS05.10, DSS06.10, 3.1.10, CCI-000057, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, SR 1.1, SR 1.10, SR 1.2, SR 1.5, SR 1.7, SR 1.8, SR 1.9, A.18.1.4, A.9.2.1, A.9.2.4, A.9.3.1, A.9.4.2, A.9.4.3, CM-6(a), PR.AC-7, FMT_MOF_EXT.1, SRG-OS-000029-GPOS-00010

Description
If not already configured, ensure that users cannot change GNOME3 screensaver lock settings by adding /org/gnome/desktop/screensaver/lock-delay to /etc/dconf/db/local.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/desktop/screensaver/lock-delay
After the settings have been set, run dconf update.
Rationale
A session time-out lock is a temporary action taken when a user stops work and moves away from the immediate physical vicinity of the information system but does not logout because of the temporary nature of the absence. Rather than relying on the user to manually lock their operating system session prior to vacating the vicinity, GNOME desktops can be configured to identify when a user's session has idled and take action to initiate the session lock. As such, users should not be allowed to change session settings.
Ensure Users Cannot Change GNOME3 Session Idle Settingsxccdf_org.ssgproject.content_rule_dconf_gnome_session_idle_user_locks medium

Ensure Users Cannot Change GNOME3 Session Idle Settings

Rule IDxccdf_org.ssgproject.content_rule_dconf_gnome_session_idle_user_locks
Result
notapplicable
Multi-check ruleno
Time2024-12-29T17:33:54+01:00
Severitymedium
Identifiers and References

References:  1, 12, 15, 16, DSS05.04, DSS05.10, DSS06.10, 3.1.10, CCI-000057, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, SR 1.1, SR 1.10, SR 1.2, SR 1.5, SR 1.7, SR 1.8, SR 1.9, A.18.1.4, A.9.2.1, A.9.2.4, A.9.3.1, A.9.4.2, A.9.4.3, CM-6(a), PR.AC-7, FMT_MOF_EXT.1, SRG-OS-000029-GPOS-00010

Description
If not already configured, ensure that users cannot change GNOME3 session idle settings by adding /org/gnome/desktop/session/idle-delay to /etc/dconf/db/local.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/desktop/session/idle-delay
After the settings have been set, run dconf update.
Rationale
A session time-out lock is a temporary action taken when a user stops work and moves away from the immediate physical vicinity of the information system but does not logout because of the temporary nature of the absence. Rather than relying on the user to manually lock their operating system session prior to vacating the vicinity, GNOME desktops can be configured to identify when a user's session has idled and take action to initiate the session lock. As such, users should not be allowed to change session settings.
Make sure that the dconf databases are up-to-date with regards to respective keyfilesxccdf_org.ssgproject.content_rule_dconf_db_up_to_date high

Make sure that the dconf databases are up-to-date with regards to respective keyfiles

Rule IDxccdf_org.ssgproject.content_rule_dconf_db_up_to_date
Result
notapplicable
Multi-check ruleno
Time2024-12-29T17:33:54+01:00
Severityhigh
Identifiers and References

References:  164.308(a)(1)(ii)(B), 164.308(a)(5)(ii)(A), SRG-OS-000480-GPOS-00227

Description
By default, DConf uses a binary database as a data backend. The system-level database is compiled from keyfiles in the /etc/dconf/db/ directory by the
dconf update
command. More specifically, content present in the following directories:
/etc/dconf/db/distro.d
/etc/dconf/db/local.d
Rationale
Unlike text-based keyfiles, the binary database is impossible to check by OVAL. Therefore, in order to evaluate dconf configuration, both have to be true at the same time - configuration files have to be compliant, and the database needs to be more recent than those keyfiles, which gives confidence that it reflects them.
Install dnf-automatic Packagexccdf_org.ssgproject.content_rule_package_dnf-automatic_installed medium

Install dnf-automatic Package

Rule IDxccdf_org.ssgproject.content_rule_package_dnf-automatic_installed
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-package_dnf-automatic_installed:def:1
Time2024-12-29T17:33:54+01:00
Severitymedium
Identifiers and References

References:  BP28(R8), SRG-OS-000191-GPOS-00080

Description
The dnf-automatic package can be installed with the following command:
$ sudo dnf install dnf-automatic
Rationale
dnf-automatic is an alternative command line interface (CLI) to dnf upgrade suitable for automatic, regular execution.

Complexity:low
Disruption:low
Strategy:enable

if ! rpm -q --quiet "dnf-automatic" ; then
    dnf install -y "dnf-automatic"
fi

Complexity:low
Disruption:low
Strategy:enable
- name: Ensure dnf-automatic is installed
  package:
    name: dnf-automatic
    state: present
  tags:
    - enable_strategy
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - package_dnf-automatic_installed

Complexity:low
Disruption:low
Strategy:enable
include install_dnf-automatic

class install_dnf-automatic {
  package { 'dnf-automatic':
    ensure => 'installed',
  }
}

Complexity:low
Disruption:low
Strategy:enable

package --add=dnf-automatic


[[packages]]
name = "dnf-automatic"
version = "*"
OVAL test results details

package dnf-automatic is installed  oval:ssg-test_package_dnf-automatic_installed:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_test_package_dnf-automatic_installed:obj:1 of type rpminfo_object
Name
dnf-automatic
Configure dnf-automatic to Install Available Updates Automaticallyxccdf_org.ssgproject.content_rule_dnf-automatic_apply_updates medium

Configure dnf-automatic to Install Available Updates Automatically

Rule IDxccdf_org.ssgproject.content_rule_dnf-automatic_apply_updates
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-dnf-automatic_apply_updates:def:1
Time2024-12-29T17:33:54+01:00
Severitymedium
Identifiers and References

References:  BP28(R8), 0940, 1144, 1467, 1472, 1483, 1493, 1494, 1495, SI-2(5), CM-6(a), SI-2(c), FMT_SMF_EXT.1, SRG-OS-000191-GPOS-00080

Description
To ensure that the packages comprising the available updates will be automatically installed by dnf-automatic, set apply_updates to yes under [commands] section in /etc/dnf/automatic.conf.
Rationale
Installing software updates is a fundamental mitigation against the exploitation of publicly-known vulnerabilities. If the most recent security patches and updates are not installed, unauthorized users may take advantage of weaknesses in the unpatched software. The lack of prompt attention to patching could result in a system compromise. The automated installation of updates ensures that recent security patches are applied in a timely manner.


found=false

# set value in all files if they contain section or key
for f in $(echo -n "/etc/dnf/automatic.conf"); do
    if [ ! -e "$f" ]; then
        continue
    fi

    # find key in section and change value
    if grep -qzosP "[[:space:]]*\[commands\]([^\n\[]*\n+)+?[[:space:]]*apply_updates" "$f"; then
            sed -i "s/apply_updates[^(\n)]*/apply_updates = yes/" "$f"
            found=true

    # find section and add key = value to it
    elif grep -qs "[[:space:]]*\[commands\]" "$f"; then
            sed -i "/[[:space:]]*commands/a apply_updates = yes" "$f"
            found=true
    fi
done

# if section not in any file, append section with key = value to FIRST file in files parameter
if ! $found ; then
    file=$(echo "/etc/dnf/automatic.conf" | cut -f1 -d' ')
    mkdir -p "$(dirname "$file")"
    echo -e "[commands]\napply_updates = yes" >> "$file"
fi

Complexity:low
Disruption:medium
- name: Configure dnf-automatic to Install Available Updates Automatically
  ini_file:
    dest: /etc/dnf/automatic.conf
    section: commands
    option: apply_updates
    value: 'yes'
    create: true
  tags:
    - NIST-800-53-CM-6(a)
    - NIST-800-53-SI-2(5)
    - NIST-800-53-SI-2(c)
    - dnf-automatic_apply_updates
    - low_complexity
    - medium_disruption
    - medium_severity
    - no_reboot_needed
    - unknown_strategy
OVAL test results details

tests the value of apply_updates setting in the /etc/dnf/automatic.conf file  oval:ssg-test_dnf-automatic_apply_updates:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_dnf-automatic_apply_updates:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/dnf/automatic.conf^\s*\[commands\].*(?:\n\s*[^[\s].*)*\n^\s*apply_updates[ \t]*=[ \t]*(.+?)[ \t]*(?:$|#)1

The configuration file /etc/dnf/automatic.conf exists for dnf-automatic_apply_updates  oval:ssg-test_dnf-automatic_apply_updates_config_file_exists:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_dnf-automatic_apply_updates_config_file:obj:1 of type file_object
Filepath
^/etc/dnf/automatic.conf
Configure dnf-automatic to Install Only Security Updatesxccdf_org.ssgproject.content_rule_dnf-automatic_security_updates_only low

Configure dnf-automatic to Install Only Security Updates

Rule IDxccdf_org.ssgproject.content_rule_dnf-automatic_security_updates_only
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-dnf-automatic_security_updates_only:def:1
Time2024-12-29T17:33:54+01:00
Severitylow
Identifiers and References

References:  BP28(R8), SI-2(5), CM-6(a), SI-2(c), FMT_SMF_EXT.1, SRG-OS-000191-GPOS-00080

Description
To configure dnf-automatic to install only security updates automatically, set upgrade_type to security under [commands] section in /etc/dnf/automatic.conf.
Rationale
By default, dnf-automatic installs all available updates. Reducing the amount of updated packages only to updates that were issued as a part of a security advisory increases the system stability.


found=false

# set value in all files if they contain section or key
for f in $(echo -n "/etc/dnf/automatic.conf"); do
    if [ ! -e "$f" ]; then
        continue
    fi

    # find key in section and change value
    if grep -qzosP "[[:space:]]*\[commands\]([^\n\[]*\n+)+?[[:space:]]*upgrade_type" "$f"; then
            sed -i "s/upgrade_type[^(\n)]*/upgrade_type = security/" "$f"
            found=true

    # find section and add key = value to it
    elif grep -qs "[[:space:]]*\[commands\]" "$f"; then
            sed -i "/[[:space:]]*commands/a upgrade_type = security" "$f"
            found=true
    fi
done

# if section not in any file, append section with key = value to FIRST file in files parameter
if ! $found ; then
    file=$(echo "/etc/dnf/automatic.conf" | cut -f1 -d' ')
    mkdir -p "$(dirname "$file")"
    echo -e "[commands]\nupgrade_type = security" >> "$file"
fi

Complexity:low
Disruption:medium
- name: Configure dnf-automatic to Install Only Security Updates
  ini_file:
    dest: /etc/dnf/automatic.conf
    section: commands
    option: upgrade_type
    value: security
    create: true
  tags:
    - NIST-800-53-CM-6(a)
    - NIST-800-53-SI-2(5)
    - NIST-800-53-SI-2(c)
    - dnf-automatic_security_updates_only
    - low_complexity
    - low_severity
    - medium_disruption
    - no_reboot_needed
    - unknown_strategy
OVAL test results details

tests the value of upgrade_type setting in the /etc/dnf/automatic.conf file  oval:ssg-test_dnf-automatic_security_updates_only:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_dnf-automatic_security_updates_only:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/dnf/automatic.conf^\s*\[commands\].*(?:\n\s*[^[\s].*)*\n^\s*upgrade_type[ \t]*=[ \t]*(.+?)[ \t]*(?:$|#)1

The configuration file /etc/dnf/automatic.conf exists for dnf-automatic_security_updates_only  oval:ssg-test_dnf-automatic_security_updates_only_config_file_exists:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_dnf-automatic_security_updates_only_config_file:obj:1 of type file_object
Filepath
^/etc/dnf/automatic.conf
Ensure Fedora GPG Key Installedxccdf_org.ssgproject.content_rule_ensure_fedora_gpgkey_installed high

Ensure Fedora GPG Key Installed

Rule IDxccdf_org.ssgproject.content_rule_ensure_fedora_gpgkey_installed
Result
pass
Multi-check ruleno
OVAL Definition IDoval:ssg-ensure_fedora_gpgkey_installed:def:1
Time2024-12-29T17:33:55+01:00
Severityhigh
Identifiers and References

References:  11, 2, 3, 9, 5.10.4.1, APO01.06, BAI03.05, BAI06.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS06.02, 3.4.8, CCI-001749, 164.308(a)(1)(ii)(D), 164.312(b), 164.312(c)(1), 164.312(c)(2), 164.312(e)(2)(i), 4.3.4.3.2, 4.3.4.3.3, 4.3.4.4.4, SR 3.1, SR 3.3, SR 3.4, SR 3.8, SR 7.6, A.11.2.4, A.12.1.2, A.12.2.1, A.12.5.1, A.12.6.2, A.14.1.2, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4, CM-5(3), SI-7, SC-12, SC-12(3), CM-6(a), PR.DS-6, PR.DS-8, PR.IP-1, Req-6.2

Description
To ensure the system can cryptographically verify base software packages come from Fedora (and to connect to the Fedora Network to receive them), the Fedora GPG key must properly be installed. To install the Fedora GPG key, run one of the commands below, depending on your Fedora vesion:
$ sudo rpm --import /etc/pki/rpm-gpg/RPM-GPG-KEY-fedora-34-primary
"
$ sudo rpm --import /etc/pki/rpm-gpg/RPM-GPG-KEY-fedora-33-primary
"
Rationale
Changes to software components can have significant effects on the overall security of the operating system. This requirement ensures the software has not been tampered with and that it has been provided by a trusted vendor. The Fedora GPG key is necessary to cryptographically verify packages are from Fedora."
OVAL test results details

Test installed OS is part of the unix family  oval:ssg-test_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

Test installed OS is part of the unix family  oval:ssg-test_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

Test installed OS is part of the unix family  oval:ssg-test_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

Test installed OS is part of the unix family  oval:ssg-test_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

fedora-release RPM packages are installed  oval:ssg-test_fedora_release_rpm:tst:1  true

Following items have been found on the system:
NameArchEpochReleaseVersionEvrSignature keyidExtended name
fedora-release-identity-servernoarch(none)39340:34-391161ae6945719a39fedora-release-identity-server-0:34-39.noarch
fedora-release-commonnoarch(none)39340:34-391161ae6945719a39fedora-release-common-0:34-39.noarch
fedora-release-servernoarch(none)39340:34-391161ae6945719a39fedora-release-server-0:34-39.noarch

fedora-release RPM packages are installed  oval:ssg-test_fedora_release_rpm:tst:1  true

Following items have been found on the system:
NameArchEpochReleaseVersionEvrSignature keyidExtended name
fedora-release-identity-servernoarch(none)39340:34-391161ae6945719a39fedora-release-identity-server-0:34-39.noarch
fedora-release-servernoarch(none)39340:34-391161ae6945719a39fedora-release-server-0:34-39.noarch
fedora-release-commonnoarch(none)39340:34-391161ae6945719a39fedora-release-common-0:34-39.noarch

CPE vendor is 'fedoraproject' and 'product' is fedora  oval:ssg-test_fedora_vendor_product:tst:1  true

Following items have been found on the system:
PathContent
/etc/system-release-cpecpe:/o:fedoraproject:fedora:34

CPE vendor is 'fedoraproject' and 'product' is fedora  oval:ssg-test_fedora_vendor_product:tst:1  true

Following items have been found on the system:
PathContent
/etc/system-release-cpecpe:/o:fedoraproject:fedora:34

Test installed OS is part of the unix family  oval:ssg-test_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

Test installed OS is part of the unix family  oval:ssg-test_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

Test installed OS is part of the unix family  oval:ssg-test_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

Test installed OS is part of the unix family  oval:ssg-test_unix_family:tst:1  true

Following items have been found on the system:
Family
unix

fedora-release RPM packages are installed  oval:ssg-test_fedora_release_rpm:tst:1  true

Following items have been found on the system:
NameArchEpochReleaseVersionEvrSignature keyidExtended name
fedora-release-identity-servernoarch(none)39340:34-391161ae6945719a39fedora-release-identity-server-0:34-39.noarch
fedora-release-commonnoarch(none)39340:34-391161ae6945719a39fedora-release-common-0:34-39.noarch
fedora-release-servernoarch(none)39340:34-391161ae6945719a39fedora-release-server-0:34-39.noarch

fedora-release RPM packages are installed  oval:ssg-test_fedora_release_rpm:tst:1  true

Following items have been found on the system:
NameArchEpochReleaseVersionEvrSignature keyidExtended name
fedora-release-identity-servernoarch(none)39340:34-391161ae6945719a39fedora-release-identity-server-0:34-39.noarch
fedora-release-servernoarch(none)39340:34-391161ae6945719a39fedora-release-server-0:34-39.noarch
fedora-release-commonnoarch(none)39340:34-391161ae6945719a39fedora-release-common-0:34-39.noarch

CPE vendor is 'fedoraproject' and 'product' is fedora  oval:ssg-test_fedora_vendor_product:tst:1  true

Following items have been found on the system:
PathContent
/etc/system-release-cpecpe:/o:fedoraproject:fedora:34

CPE vendor is 'fedoraproject' and 'product' is fedora  oval:ssg-test_fedora_vendor_product:tst:1  true

Following items have been found on the system:
PathContent
/etc/system-release-cpecpe:/o:fedoraproject:fedora:34

Fedora 38ab71f4 release key package is installed  oval:ssg-test_package_gpgkey-38ab71f4-60242b08_installed:tst:1  false

Following items have been found on the system:
NameArchEpochReleaseVersionEvrSignature keyidExtended name
gpg-pubkey(none)(none)5f2c019245719a390:45719a39-5f2c01920gpg-pubkey-0:45719a39-5f2c0192.(none)

Fedora 9867c58f release key package is installed  oval:ssg-test_package_gpgkey-9867c58f-601c49ca_installed:tst:1  false

Following items have been found on the system:
NameArchEpochReleaseVersionEvrSignature keyidExtended name
gpg-pubkey(none)(none)5f2c019245719a390:45719a39-5f2c01920gpg-pubkey-0:45719a39-5f2c0192.(none)

Fedora 45719a39 release key package is installed  oval:ssg-test_package_gpgkey-45719a39-5f2c0192_installed:tst:1  true

Following items have been found on the system:
NameArchEpochReleaseVersionEvrSignature keyidExtended name
gpg-pubkey(none)(none)5f2c019245719a390:45719a39-5f2c01920gpg-pubkey-0:45719a39-5f2c0192.(none)

Fedora 9570ff31 release key package is installed  oval:ssg-test_package_gpgkey-9570ff31-5e3006fb_installed:tst:1  false

Following items have been found on the system:
NameArchEpochReleaseVersionEvrSignature keyidExtended name
gpg-pubkey(none)(none)5f2c019245719a390:45719a39-5f2c01920gpg-pubkey-0:45719a39-5f2c0192.(none)
Ensure gpgcheck Enabled In Main dnf Configurationxccdf_org.ssgproject.content_rule_ensure_gpgcheck_globally_activated high

Ensure gpgcheck Enabled In Main dnf Configuration

Rule IDxccdf_org.ssgproject.content_rule_ensure_gpgcheck_globally_activated
Result
pass
Multi-check ruleno
OVAL Definition IDoval:ssg-ensure_gpgcheck_globally_activated:def:1
Time2024-12-29T17:33:55+01:00
Severityhigh
Identifiers and References

References:  BP28(R15), 11, 2, 3, 9, 5.10.4.1, APO01.06, BAI03.05, BAI06.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS06.02, 3.4.8, CCI-001749, 164.308(a)(1)(ii)(D), 164.312(b), 164.312(c)(1), 164.312(c)(2), 164.312(e)(2)(i), 4.3.4.3.2, 4.3.4.3.3, 4.3.4.4.4, SR 3.1, SR 3.3, SR 3.4, SR 3.8, SR 7.6, A.11.2.4, A.12.1.2, A.12.2.1, A.12.5.1, A.12.6.2, A.14.1.2, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4, CM-5(3), SI-7, SC-12, SC-12(3), CM-6(a), SA-12, SA-12(10), CM-11(a), CM-11(b), PR.DS-6, PR.DS-8, PR.IP-1, FPT_TUD_EXT.1, FPT_TUD_EXT.2, Req-6.2, SRG-OS-000366-GPOS-00153, SRG-OS-000366-VMM-001430, SRG-OS-000370-VMM-001460, SRG-OS-000404-VMM-001650

Description
The gpgcheck option controls whether RPM packages' signatures are always checked prior to installation. To configure dnf to check package signatures before installing them, ensure the following line appears in /etc/dnf/dnf.conf in the [main] section:
gpgcheck=1
Rationale
Changes to any software components can have significant effects on the overall security of the operating system. This requirement ensures the software has not been tampered with and that it has been provided by a trusted vendor.
Accordingly, patches, service packs, device drivers, or operating system components must be signed with a certificate recognized and approved by the organization.
Verifying the authenticity of the software prior to installation validates the integrity of the patch or upgrade received from a vendor. This ensures the software has not been tampered with and that it has been provided by a trusted vendor. Self-signed certificates are disallowed by this requirement. Certificates used to verify the software must be from an approved Certificate Authority (CA).
OVAL test results details

check value of gpgcheck in /etc/dnf/dnf.conf  oval:ssg-test_ensure_gpgcheck_globally_activated:tst:1  true

Following items have been found on the system:
PathContent
/etc/dnf/dnf.confgpgcheck=1
Ensure gpgcheck Enabled for Local Packagesxccdf_org.ssgproject.content_rule_ensure_gpgcheck_local_packages high

Ensure gpgcheck Enabled for Local Packages

Rule IDxccdf_org.ssgproject.content_rule_ensure_gpgcheck_local_packages
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-ensure_gpgcheck_local_packages:def:1
Time2024-12-29T17:33:55+01:00
Severityhigh
Identifiers and References

References:  BP28(R15), 11, 3, 9, BAI10.01, BAI10.02, BAI10.03, BAI10.05, 3.4.8, CCI-001749, 164.308(a)(1)(ii)(D), 164.312(b), 164.312(c)(1), 164.312(c)(2), 164.312(e)(2)(i), 4.3.4.3.2, 4.3.4.3.3, SR 7.6, A.12.1.2, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4, CM-11(a), CM-11(b), CM-6(a), CM-5(3), SA-12, SA-12(10), PR.IP-1, FPT_TUD_EXT.1, FPT_TUD_EXT.2, SRG-OS-000366-GPOS-00153, SRG-OS-000366-VMM-001430, SRG-OS-000370-VMM-001460, SRG-OS-000404-VMM-001650

Description
dnf should be configured to verify the signature(s) of local packages prior to installation. To configure dnf to verify signatures of local packages, set the localpkg_gpgcheck to 1 in /etc/dnf/dnf.conf.
Rationale
Changes to any software components can have significant effects to the overall security of the operating system. This requirement ensures the software has not been tampered and has been provided by a trusted vendor.

Accordingly, patches, service packs, device drivers, or operating system components must be signed with a certificate recognized and approved by the organization.

# Remediation is applicable only in certain platforms
if rpm --quiet -q yum; then

# Test if the config_file is a symbolic link. If so, use --follow-symlinks with sed.
# Otherwise, regular sed command will do.
sed_command=('sed' '-i')
if test -L "/etc/dnf/dnf.conf"; then
    sed_command+=('--follow-symlinks')
fi

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^localpkg_gpgcheck")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "1"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^localpkg_gpgcheck\\>" "/etc/dnf/dnf.conf"; then
    "${sed_command[@]}" "s/^localpkg_gpgcheck\\>.*/$formatted_output/gi" "/etc/dnf/dnf.conf"
else
    # \n is precaution for case where file ends without trailing newline
    
    printf '%s\n' "$formatted_output" >> "/etc/dnf/dnf.conf"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:medium
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.4.8
    - NIST-800-53-CM-11(a)
    - NIST-800-53-CM-11(b)
    - NIST-800-53-CM-5(3)
    - NIST-800-53-CM-6(a)
    - NIST-800-53-SA-12
    - NIST-800-53-SA-12(10)
    - ensure_gpgcheck_local_packages
    - high_severity
    - low_complexity
    - medium_disruption
    - no_reboot_needed
    - unknown_strategy

- name: Ensure GPG check Enabled for Local Packages (Yum)
  ini_file:
    dest: /etc/dnf/dnf.conf
    section: main
    option: localpkg_gpgcheck
    value: 1
    no_extra_spaces: true
    create: true
  when: '"yum" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.4.8
    - NIST-800-53-CM-11(a)
    - NIST-800-53-CM-11(b)
    - NIST-800-53-CM-5(3)
    - NIST-800-53-CM-6(a)
    - NIST-800-53-SA-12
    - NIST-800-53-SA-12(10)
    - ensure_gpgcheck_local_packages
    - high_severity
    - low_complexity
    - medium_disruption
    - no_reboot_needed
    - unknown_strategy
OVAL test results details

check value of localpkg_gpgcheck in /etc/dnf/dnf.conf  oval:ssg-test_yum_ensure_gpgcheck_local_packages:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_yum_ensure_gpgcheck_local_packages:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/dnf/dnf.conf^\s*localpkg_gpgcheck\s*=\s*(1|True|yes)\s*$1
Ensure gpgcheck Enabled for All dnf Package Repositoriesxccdf_org.ssgproject.content_rule_ensure_gpgcheck_never_disabled high

Ensure gpgcheck Enabled for All dnf Package Repositories

Rule IDxccdf_org.ssgproject.content_rule_ensure_gpgcheck_never_disabled
Result
pass
Multi-check ruleno
OVAL Definition IDoval:ssg-ensure_gpgcheck_never_disabled:def:1
Time2024-12-29T17:33:55+01:00
Severityhigh
Identifiers and References

References:  BP28(R15), 11, 2, 3, 9, 5.10.4.1, APO01.06, BAI03.05, BAI06.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS06.02, 3.4.8, CCI-001749, 164.308(a)(1)(ii)(D), 164.312(b), 164.312(c)(1), 164.312(c)(2), 164.312(e)(2)(i), 4.3.4.3.2, 4.3.4.3.3, 4.3.4.4.4, SR 3.1, SR 3.3, SR 3.4, SR 3.8, SR 7.6, A.11.2.4, A.12.1.2, A.12.2.1, A.12.5.1, A.12.6.2, A.14.1.2, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4, CM-5(3), SI-7, SC-12, SC-12(3), CM-6(a), SA-12, SA-12(10), CM-11(a), CM-11(b), PR.DS-6, PR.DS-8, PR.IP-1, FPT_TUD_EXT.1, FPT_TUD_EXT.2, Req-6.2, SRG-OS-000366-GPOS-00153, SRG-OS-000366-VMM-001430, SRG-OS-000370-VMM-001460, SRG-OS-000404-VMM-001650

Description
To ensure signature checking is not disabled for any repos, remove any lines from files in /etc/yum.repos.d of the form:
gpgcheck=0
Rationale
Verifying the authenticity of the software prior to installation validates the integrity of the patch or upgrade received from a vendor. This ensures the software has not been tampered with and that it has been provided by a trusted vendor. Self-signed certificates are disallowed by this requirement. Certificates used to verify the software must be from an approved Certificate Authority (CA)."
OVAL test results details

check for existence of gpgcheck=0 in /etc/yum.repos.d/ files  oval:ssg-test_ensure_gpgcheck_never_disabled:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-obj_ensure_gpgcheck_never_disabled:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/etc/yum.repos.d.*^\s*gpgcheck\s*=\s*0\s*$1
Enable dnf-automatic Timerxccdf_org.ssgproject.content_rule_timer_dnf-automatic_enabled medium

Enable dnf-automatic Timer

Rule IDxccdf_org.ssgproject.content_rule_timer_dnf-automatic_enabled
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-timer_dnf-automatic_enabled:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  BP28(R8), SI-2(5), CM-6(a), SI-2(c), FMT_SMF_EXT.1, SRG-OS-000191-GPOS-00080

Description
The dnf-automatic timer can be enabled with the following command:
$ sudo systemctl enable dnf-automatic.timer
Rationale
The dnf-automatic is an alternative command line interface (CLI) to dnf upgrade with specific facilities to make it suitable to be executed automatically and regularly from systemd timers, cron jobs and similar. The tool is controlled by dnf-automatic.timer SystemD timer.

Complexity:low
Disruption:low
Strategy:enable

SYSTEMCTL_EXEC='/usr/bin/systemctl'
"$SYSTEMCTL_EXEC" start 'dnf-automatic.timer'
"$SYSTEMCTL_EXEC" enable 'dnf-automatic.timer'

Complexity:low
Disruption:low
Strategy:enable
- name: Enable timer dnf-automatic
  block:

    - name: Gather the package facts
      package_facts:
        manager: auto

    - name: Enable timer dnf-automatic
      systemd:
        name: dnf-automatic.timer
        enabled: 'yes'
        state: started
      when:
        - '"dnf-automatic" in ansible_facts.packages'
  tags:
    - NIST-800-53-CM-6(a)
    - NIST-800-53-SI-2(5)
    - NIST-800-53-SI-2(c)
    - enable_strategy
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - timer_dnf-automatic_enabled
OVAL test results details

package dnf-automatic is installed  oval:ssg-test_package_dnf-automatic_installed:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_test_package_dnf-automatic_installed:obj:1 of type rpminfo_object
Name
dnf-automatic

Test that the dnf-automatic timer is running  oval:ssg-test_timer_running_dnf-automatic:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_timer_running_dnf-automatic:obj:1 of type systemdunitproperty_object
UnitProperty
dnf-automatic\.timerActiveState

systemd test  oval:ssg-test_multi_user_wants_dnf-automatic:tst:1  false

Following items have been found on the system:
UnitDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependency
multi-user.targetbasic.target-.mountsysinit.targetlvm2-lvmpolld.socketsystemd-update-utmp.servicesys-kernel-config.mountcryptsetup.targetsystemd-tmpfiles-setup-dev.servicesystemd-udevd.serviceveritysetup.targetsystemd-ask-password-console.pathsystemd-journal-catalog-update.serviceselinux-autorelabel-mark.servicesystemd-journald.serviceplymouth-start.servicelocal-fs.targetboot.mountsystemd-remount-fs.servicetmp.mountsystemd-repart.serviceswap.targetdev-zram0.swapsystemd-firstboot.servicedracut-shutdown.serviceplymouth-read-write.servicesystemd-udev-trigger.serviceimport-state.servicesystemd-sysctl.servicesystemd-sysusers.serviceproc-sys-fs-binfmt_misc.automountsystemd-journal-flush.servicemultipathd.servicelvm2-monitor.servicedev-hugepages.mountsystemd-update-done.servicesystemd-random-seed.servicedev-mqueue.mountsystemd-hwdb-update.serviceldconfig.servicesystemd-boot-system-token.servicesystemd-machine-id-commit.servicesystemd-tmpfiles-setup.servicesys-kernel-debug.mountiscsi-onboot.servicesys-fs-fuse-connections.mountsys-kernel-tracing.mountkmod-static-nodes.servicesystemd-modules-load.servicesystemd-binfmt.servicepaths.targetrpmdb-rebuild.servicetimers.targetfstrim.timersystemd-tmpfiles-clean.timerlogrotate.timerraid-check.timerdnf-makecache.timermlocate-updatedb.timerunbound-anchor.timerslices.targetsystem.slice-.slicesockets.targetcockpit.socketmultipathd.socketsystemd-udevd-control.socketdbus.socketsystemd-journald-dev-log.socketsssd-kcm.socketsystemd-initctl.socketpcscd.socketsystemd-userdbd.socketiscsid.socketsystemd-coredump.socketdm-event.socketsystemd-udevd-kernel.socketiscsiuio.socketsystemd-journald-audit.socketsystemd-journald.socketsssd.serviceatd.servicegetty.targetgetty@tty1.servicemcelog.serviceabrt-xorg.servicefirewalld.serviceabrt-oops.servicesystemd-resolved.servicesystemd-ask-password-wall.pathrsyslog.serviceabrtd.servicesshd.serviceabrt-journal-core.servicesystemd-update-utmp-runlevel.servicesystemd-oomd.serviceirqbalance.serviceModemManager.serviceplymouth-quit.servicesystemd-logind.servicesmartd.serviceauditd.servicechronyd.serviceremote-fs.targetiscsi.servicenfs-client.targetremote-fs-pre.targetauth-rpcgss-module.servicerpc-statd-notify.servicesystemd-homed.serviceplymouth-quit-wait.servicemdmonitor.serviceNetworkManager.serviceabrt-vmcore.servicesystemd-user-sessions.service
Enable GNOME3 Login Warning Bannerxccdf_org.ssgproject.content_rule_dconf_gnome_banner_enabled medium

Enable GNOME3 Login Warning Banner

Rule IDxccdf_org.ssgproject.content_rule_dconf_gnome_banner_enabled
Result
notapplicable
Multi-check ruleno
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 12, 15, 16, DSS05.04, DSS05.10, DSS06.10, 3.1.9, CCI-000048, CCI-000050, CCI-001384, CCI-001385, CCI-001386, CCI-001387, CCI-001388, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, SR 1.1, SR 1.10, SR 1.2, SR 1.5, SR 1.7, SR 1.8, SR 1.9, A.18.1.4, A.9.2.1, A.9.2.4, A.9.3.1, A.9.4.2, A.9.4.3, AC-8(a), AC-8(b), AC-8(c), PR.AC-7, FMT_MOF_EXT.1, SRG-OS-000023-GPOS-00006, SRG-OS-000024-GPOS-00007, SRG-OS-000228-GPOS-00088

Description
In the default graphical environment, displaying a login warning banner in the GNOME Display Manager's login screen can be enabled on the login screen by setting banner-message-enable to true.

To enable, add or edit banner-message-enable to /etc/dconf/db/distro.d/00-security-settings. For example:
[org/gnome/login-screen]
banner-message-enable=true
Once the setting has been added, add a lock to /etc/dconf/db/distro.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/login-screen/banner-message-enable
After the settings have been set, run dconf update. The banner text must also be set.
Rationale
Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance.

For U.S. Government systems, system use notifications are required only for access via login interfaces with human users and are not required when such human interfaces do not exist.
Modify the System Login Bannerxccdf_org.ssgproject.content_rule_banner_etc_issue medium

Modify the System Login Banner

Rule IDxccdf_org.ssgproject.content_rule_banner_etc_issue
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-banner_etc_issue:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 12, 15, 16, DSS05.04, DSS05.10, DSS06.10, 3.1.9, CCI-000048, CCI-000050, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, SR 1.1, SR 1.10, SR 1.2, SR 1.5, SR 1.7, SR 1.8, SR 1.9, A.18.1.4, A.9.2.1, A.9.2.4, A.9.3.1, A.9.4.2, A.9.4.3, AC-8(a), AC-8(c), PR.AC-7, FMT_MOF_EXT.1, SRG-OS-000023-GPOS-00006, SRG-OS-000024-GPOS-00007, SRG-OS-000023-VMM-000060, SRG-OS-000024-VMM-000070

Description
To configure the system login banner edit /etc/issue. Replace the default text with a message compliant with the local site policy or a legal disclaimer. The DoD required text is either:

You are accessing a U.S. Government (USG) Information System (IS) that is provided for USG-authorized use only. By using this IS (which includes any device attached to this IS), you consent to the following conditions:
-The USG routinely intercepts and monitors communications on this IS for purposes including, but not limited to, penetration testing, COMSEC monitoring, network operations and defense, personnel misconduct (PM), law enforcement (LE), and counterintelligence (CI) investigations.
-At any time, the USG may inspect and seize data stored on this IS.
-Communications using, or data stored on, this IS are not private, are subject to routine monitoring, interception, and search, and may be disclosed or used for any USG-authorized purpose.
-This IS includes security measures (e.g., authentication and access controls) to protect USG interests -- not for your personal benefit or privacy.
-Notwithstanding the above, using this IS does not constitute consent to PM, LE or CI investigative searching or monitoring of the content of privileged communications, or work product, related to personal representation or services by attorneys, psychotherapists, or clergy, and their assistants. Such communications and work product are private and confidential. See User Agreement for details.


OR:

I've read & consent to terms in IS user agreem't.
Rationale
Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance.

System use notifications are required only for access via login interfaces with human users and are not required when such human interfaces do not exist.

# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

login_banner_text='^\-\-[\s\n]+WARNING[\s\n]+\-\-[\s\n]+This[\s\n]+system[\s\n]+is[\s\n]+for[\s\n]+the[\s\n]+use[\s\n]+of[\s\n]+authorized[\s\n]+users[\s\n]+only\.[\s\n]+Individuals[\s\n]+using[\s\n]+this[\s\n]+computer[\s\n]+system[\s\n]+without[\s\n]+authority[\s\n]+or[\s\n]+in[\s\n]+excess[\s\n]+of[\s\n]+their[\s\n]+authority[\s\n]+are[\s\n]+subject[\s\n]+to[\s\n]+having[\s\n]+all[\s\n]+their[\s\n]+activities[\s\n]+on[\s\n]+this[\s\n]+system[\s\n]+monitored[\s\n]+and[\s\n]+recorded[\s\n]+by[\s\n]+system[\s\n]+personnel\.[\s\n]+Anyone[\s\n]+using[\s\n]+this[\s\n]+system[\s\n]+expressly[\s\n]+consents[\s\n]+to[\s\n]+such[\s\n]+monitoring[\s\n]+and[\s\n]+is[\s\n]+advised[\s\n]+that[\s\n]+if[\s\n]+such[\s\n]+monitoring[\s\n]+reveals[\s\n]+possible[\s\n]+evidence[\s\n]+of[\s\n]+criminal[\s\n]+activity[\s\n]+system[\s\n]+personal[\s\n]+may[\s\n]+provide[\s\n]+the[\s\n]+evidence[\s\n]+of[\s\n]+such[\s\n]+monitoring[\s\n]+to[\s\n]+law[\s\n]+enforcement[\s\n]+officials\.$'


# Multiple regexes transform the banner regex into a usable banner
# 0 - Remove anchors around the banner text
login_banner_text=$(echo "$login_banner_text" | sed 's/^\^\(.*\)\$$/\1/g')
# 1 - Keep only the first banners if there are multiple
#    (dod_banners contains the long and short banner)
login_banner_text=$(echo "$login_banner_text" | sed 's/^(\(.*\.\)|.*)$/\1/g')
# 2 - Add spaces ' '. (Transforms regex for "space or newline" into a " ")
login_banner_text=$(echo "$login_banner_text" | sed 's/\[\\s\\n\]+/ /g')
# 3 - Adds newlines. (Transforms "(?:\[\\n\]+|(?:\\n)+)" into "\n")
login_banner_text=$(echo "$login_banner_text" | sed 's/(?:\[\\n\]+|(?:\\\\n)+)/\n/g')
# 4 - Remove any leftover backslash. (From any parethesis in the banner, for example).
login_banner_text=$(echo "$login_banner_text" | sed 's/\\//g')
formatted=$(echo "$login_banner_text" | fold -sw 80)

cat <<EOF >/etc/issue
$formatted
EOF

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:medium
- name: XCCDF Value login_banner_text # promote to variable
  set_fact:
    login_banner_text: !!str ^\-\-[\s\n]+WARNING[\s\n]+\-\-[\s\n]+This[\s\n]+system[\s\n]+is[\s\n]+for[\s\n]+the[\s\n]+use[\s\n]+of[\s\n]+authorized[\s\n]+users[\s\n]+only\.[\s\n]+Individuals[\s\n]+using[\s\n]+this[\s\n]+computer[\s\n]+system[\s\n]+without[\s\n]+authority[\s\n]+or[\s\n]+in[\s\n]+excess[\s\n]+of[\s\n]+their[\s\n]+authority[\s\n]+are[\s\n]+subject[\s\n]+to[\s\n]+having[\s\n]+all[\s\n]+their[\s\n]+activities[\s\n]+on[\s\n]+this[\s\n]+system[\s\n]+monitored[\s\n]+and[\s\n]+recorded[\s\n]+by[\s\n]+system[\s\n]+personnel\.[\s\n]+Anyone[\s\n]+using[\s\n]+this[\s\n]+system[\s\n]+expressly[\s\n]+consents[\s\n]+to[\s\n]+such[\s\n]+monitoring[\s\n]+and[\s\n]+is[\s\n]+advised[\s\n]+that[\s\n]+if[\s\n]+such[\s\n]+monitoring[\s\n]+reveals[\s\n]+possible[\s\n]+evidence[\s\n]+of[\s\n]+criminal[\s\n]+activity[\s\n]+system[\s\n]+personal[\s\n]+may[\s\n]+provide[\s\n]+the[\s\n]+evidence[\s\n]+of[\s\n]+such[\s\n]+monitoring[\s\n]+to[\s\n]+law[\s\n]+enforcement[\s\n]+officials\.$
  tags:
    - always

- name: Modify the System Login Banner - ensure correct banner
  copy:
    dest: /etc/issue
    content: '{{ login_banner_text | regex_replace("^\^(.*)\$$", "\1") | regex_replace("^\((.*\.)\|.*\)$",
      "\1") | regex_replace("\[\\s\\n\]\+"," ") | regex_replace("\(\?:\[\\n\]\+\|\(\?:\\\\n\)\+\)",
      "\n") | regex_replace("\\", "") | wordwrap() }}'
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-171-3.1.9
    - NIST-800-53-AC-8(a)
    - NIST-800-53-AC-8(c)
    - banner_etc_issue
    - low_complexity
    - medium_disruption
    - medium_severity
    - no_reboot_needed
    - unknown_strategy
OVAL test results details

correct banner in /etc/issue  oval:ssg-test_banner_etc_issue:tst:1  false

Following items have been found on the system:
PathContent
/etc/issue\S Kernel \r on an \m (\l)
/etc/issue.d/cockpit.issueActivate the web console with: systemctl enable --now cockpit.socket
Lock Accounts After Failed Password Attemptsxccdf_org.ssgproject.content_rule_accounts_passwords_pam_faillock_deny medium

Lock Accounts After Failed Password Attempts

Rule IDxccdf_org.ssgproject.content_rule_accounts_passwords_pam_faillock_deny
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-accounts_passwords_pam_faillock_deny:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  BP28(R18), 1, 12, 15, 16, 5.5.3, DSS05.04, DSS05.10, DSS06.10, 3.1.8, CCI-000044, CCI-002236, CCI-002237, CCI-002238, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, SR 1.1, SR 1.10, SR 1.2, SR 1.5, SR 1.7, SR 1.8, SR 1.9, 0421, 0422, 0431, 0974, 1173, 1401, 1504, 1505, 1546, 1557, 1558, 1559, 1560, 1561, A.18.1.4, A.9.2.1, A.9.2.4, A.9.3.1, A.9.4.2, A.9.4.3, CM-6(a), AC-7(a), PR.AC-7, FIA_AFL.1, Req-8.1.6, SRG-OS-000329-GPOS-00128, SRG-OS-000021-GPOS-00005, SRG-OS-000021-VMM-000050

Description
This rule configures the system to lock out accounts after a number of incorrect login attempts using pam_faillock.so. pam_faillock.so module requires multiple entries in pam files. These entries must be carefully defined to work as expected. In order to avoid any errors when manually editing these files, it is recommended to use the appropriate tools, such as authselect or authconfig, depending on the OS version.
Rationale
Locking out user accounts after a number of incorrect attempts prevents direct password guessing attacks. In combination with the silent option, user enumeration attacks are also mitigated.
Warnings
warning  If the system relies on authselect tool to manage PAM settings, the remediation will also use authselect tool. However, if any manual modification was made in PAM files, the authselect integrity check will fail and the remediation will be aborted in order to preserve intentional changes. In this case, an informative message will be shown in the remediation report. If the system supports the /etc/security/faillock.conf file, the pam_faillock parameters should be defined in faillock.conf file.

# Remediation is applicable only in certain platforms
if rpm --quiet -q pam; then

var_accounts_passwords_pam_faillock_deny='3'


if [ -f /usr/bin/authselect ]; then
    if authselect check; then
    authselect enable-feature with-faillock
    authselect apply-changes
else
    echo "
authselect integrity check failed. Remediation aborted!
This remediation could not be applied because an authselect profile was not selected or the selected profile is not intact.
It is not recommended to manually edit the PAM files when authselect tool is available.
In cases where the default authselect profile does not cover a specific demand, a custom authselect profile is recommended."
    false
fi
else
    AUTH_FILES=("/etc/pam.d/system-auth" "/etc/pam.d/password-auth")
for pam_file in "${AUTH_FILES[@]}"
do
    if ! grep -qE '^\s*auth\s+required\s+pam_faillock\.so\s+(preauth silent|authfail).*$' "$pam_file" ; then
        sed -i --follow-symlinks '/^auth.*sufficient.*pam_unix.so.*/i auth        required      pam_faillock.so preauth silent' "$pam_file"
        sed -i --follow-symlinks '/^auth.*sufficient.*pam_unix.so.*/a auth        required      pam_faillock.so authfail' "$pam_file"
        sed -i --follow-symlinks '/^account.*required.*pam_unix.so.*/i account     required      pam_faillock.so' "$pam_file"
    fi
    sed -Ei 's/(auth.*)(\[default=die\])(.*pam_faillock.so)/\1required     \3/g' "$pam_file"
done
fi
FAILLOCK_CONF="/etc/security/faillock.conf"
if [ -f $FAILLOCK_CONF ]; then
    regex="^\s*deny\s*="
    line="deny = $var_accounts_passwords_pam_faillock_deny"
    if ! grep -q $regex $FAILLOCK_CONF; then
        echo $line >> $FAILLOCK_CONF
    else
        sed -i --follow-symlinks 's/^\s*\(deny\s*=\s*\)\([0-9]\+\)/\1'"$var_accounts_passwords_pam_faillock_deny"'/g' $FAILLOCK_CONF
    fi
else
    AUTH_FILES=("/etc/pam.d/system-auth" "/etc/pam.d/password-auth")
    for pam_file in "${AUTH_FILES[@]}"
    do
        if ! grep -qE '^\s*auth.*pam_faillock.so (preauth|authfail).*deny' "$pam_file"; then
            sed -i --follow-symlinks '/^auth.*required.*pam_faillock.so.*preauth.*silent.*/ s/$/ deny='"$var_accounts_passwords_pam_faillock_deny"'/' "$pam_file"
            sed -i --follow-symlinks '/^auth.*required.*pam_faillock.so.*authfail.*/ s/$/ deny='"$var_accounts_passwords_pam_faillock_deny"'/' "$pam_file"
        else
            sed -i --follow-symlinks 's/\(^auth.*required.*pam_faillock.so.*preauth.*silent.*\)\('"deny"'=\)[0-9]\+\(.*\)/\1\2'"$var_accounts_passwords_pam_faillock_deny"'\3/' "$pam_file"
            sed -i --follow-symlinks 's/\(^auth.*required.*pam_faillock.so.*authfail.*\)\('"deny"'=\)[0-9]\+\(.*\)/\1\2'"$var_accounts_passwords_pam_faillock_deny"'\3/' "$pam_file"
        fi
    done
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - CJIS-5.5.3
    - NIST-800-171-3.1.8
    - NIST-800-53-AC-7(a)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-8.1.6
    - accounts_passwords_pam_faillock_deny
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Lock Accounts After Failed Password Attempts - Check if system relies on authselect
    tool
  ansible.builtin.stat:
    path: /usr/bin/authselect
  register: result_authselect_present
  when: '"pam" in ansible_facts.packages'
  tags:
    - CJIS-5.5.3
    - NIST-800-171-3.1.8
    - NIST-800-53-AC-7(a)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-8.1.6
    - accounts_passwords_pam_faillock_deny
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Lock Accounts After Failed Password Attempts - Remediation where authselect
    tool is present
  block:

    - name: Lock Accounts After Failed Password Attempts - Check integrity of authselect
        current profile
      ansible.builtin.command:
        cmd: authselect check
      register: result_authselect_check_cmd
      changed_when: false
      ignore_errors: true

    - name: Lock Accounts After Failed Password Attempts - Informative message based
        on the authselect integrity check result
      ansible.builtin.assert:
        that:
          - result_authselect_check_cmd is success
        fail_msg:
          - authselect integrity check failed. Remediation aborted!
          - This remediation could not be applied because an authselect profile was
            not selected or the selected profile is not intact.
          - It is not recommended to manually edit the PAM files when authselect tool
            is available.
          - In cases where the default authselect profile does not cover a specific
            demand, a custom authselect profile is recommended.
        success_msg:
          - authselect integrity check passed

    - name: Lock Accounts After Failed Password Attempts - Get authselect current
        features
      ansible.builtin.shell:
        cmd: authselect current | tail -n+3 | awk '{ print $2 }'
      register: result_authselect_features
      changed_when: false
      when:
        - result_authselect_check_cmd is success

    - name: Lock Accounts After Failed Password Attempts - Ensure with-faillock feature
        is enabled using authselect tool
      ansible.builtin.command:
        cmd: authselect enable-feature with-faillock
      register: result_authselect_cmd
      when:
        - result_authselect_check_cmd is success
        - result_authselect_features.stdout is not search("with-faillock")
  when:
    - '"pam" in ansible_facts.packages'
    - result_authselect_present.stat.exists
  tags:
    - CJIS-5.5.3
    - NIST-800-171-3.1.8
    - NIST-800-53-AC-7(a)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-8.1.6
    - accounts_passwords_pam_faillock_deny
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Lock Accounts After Failed Password Attempts - Remediation where authselect
    tool is not present
  block:

    - name: Lock Accounts After Failed Password Attempts - Check if pam_faillock.so
        is already enabled
      ansible.builtin.lineinfile:
        path: /etc/pam.d/system-auth
        regexp: .*auth.*pam_faillock.so (preauth|authfail)
        state: absent
      check_mode: true
      changed_when: false
      register: result_pam_faillock_is_enabled

    - name: Lock Accounts After Failed Password Attempts - Enable pam_faillock.so
        preauth editing PAM files
      ansible.builtin.lineinfile:
        path: '{{ item }}'
        line: auth        required      pam_faillock.so preauth
        insertbefore: ^auth.*sufficient.*pam_unix.so.*
        state: present
      loop:
        - /etc/pam.d/system-auth
        - /etc/pam.d/password-auth
      when:
        - result_pam_faillock_is_enabled.found == 0

    - name: Lock Accounts After Failed Password Attempts - Enable pam_faillock.so
        authfail editing PAM files
      ansible.builtin.lineinfile:
        path: '{{ item }}'
        line: auth        required      pam_faillock.so authfail
        insertafter: ^auth.*sufficient.*pam_unix.so.*
        state: present
      loop:
        - /etc/pam.d/system-auth
        - /etc/pam.d/password-auth
      when:
        - result_pam_faillock_is_enabled.found == 0

    - name: Lock Accounts After Failed Password Attempts - Enable pam_faillock.so
        account section editing PAM files
      ansible.builtin.lineinfile:
        path: '{{ item }}'
        line: account     required      pam_faillock.so
        insertbefore: ^account.*required.*pam_unix.so.*
        state: present
      loop:
        - /etc/pam.d/system-auth
        - /etc/pam.d/password-auth
      when:
        - result_pam_faillock_is_enabled.found == 0
  when:
    - '"pam" in ansible_facts.packages'
    - not result_authselect_present.stat.exists
  tags:
    - CJIS-5.5.3
    - NIST-800-171-3.1.8
    - NIST-800-53-AC-7(a)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-8.1.6
    - accounts_passwords_pam_faillock_deny
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
- name: XCCDF Value var_accounts_passwords_pam_faillock_deny # promote to variable
  set_fact:
    var_accounts_passwords_pam_faillock_deny: !!str 3
  tags:
    - always

- name: Lock Accounts After Failed Password Attempts - Check the presence of /etc/security/faillock.conf
    file
  ansible.builtin.stat:
    path: /etc/security/faillock.conf
  register: result_faillock_conf_check
  when: '"pam" in ansible_facts.packages'
  tags:
    - CJIS-5.5.3
    - NIST-800-171-3.1.8
    - NIST-800-53-AC-7(a)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-8.1.6
    - accounts_passwords_pam_faillock_deny
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Lock Accounts After Failed Password Attempts - Ensure the pam_faillock.so
    deny parameter in /etc/security/faillock.conf
  ansible.builtin.lineinfile:
    path: /etc/security/faillock.conf
    regexp: ^\s*deny\s*=
    line: deny = {{ var_accounts_passwords_pam_faillock_deny }}
    state: present
  when:
    - '"pam" in ansible_facts.packages'
    - result_faillock_conf_check.stat.exists
  tags:
    - CJIS-5.5.3
    - NIST-800-171-3.1.8
    - NIST-800-53-AC-7(a)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-8.1.6
    - accounts_passwords_pam_faillock_deny
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Lock Accounts After Failed Password Attempts - Ensure the pam_faillock.so
    deny parameter in PAM files
  block:

    - name: Lock Accounts After Failed Password Attempts - Check if pam_faillock.so
        deny parameter is already enabled in pam files
      ansible.builtin.lineinfile:
        path: /etc/pam.d/system-auth
        regexp: .*auth.*pam_faillock.so (preauth|authfail).*deny
        state: absent
      check_mode: true
      changed_when: false
      register: result_pam_faillock_deny_parameter_is_present

    - name: Lock Accounts After Failed Password Attempts - Ensure the inclusion of
        pam_faillock.so preauth deny parameter in auth section
      ansible.builtin.lineinfile:
        path: '{{ item }}'
        backrefs: true
        regexp: (^\s*auth\s+)([\w\[].*\b)(\s+pam_faillock.so preauth.*)
        line: \1required\3 deny={{ var_accounts_passwords_pam_faillock_deny }}
        state: present
      loop:
        - /etc/pam.d/system-auth
        - /etc/pam.d/password-auth
      when:
        - result_pam_faillock_deny_parameter_is_present.found == 0

    - name: Lock Accounts After Failed Password Attempts - Ensure the inclusion of
        pam_faillock.so authfail deny parameter in auth section
      ansible.builtin.lineinfile:
        path: '{{ item }}'
        backrefs: true
        regexp: (^\s*auth\s+)([\w\[].*\b)(\s+pam_faillock.so authfail.*)
        line: \1required\3 deny={{ var_accounts_passwords_pam_faillock_deny }}
        state: present
      loop:
        - /etc/pam.d/system-auth
        - /etc/pam.d/password-auth
      when:
        - result_pam_faillock_deny_parameter_is_present.found == 0

    - name: Lock Accounts After Failed Password Attempts - Ensure the desired value
        for pam_faillock.so preauth deny parameter in auth section
      ansible.builtin.lineinfile:
        path: '{{ item }}'
        backrefs: true
        regexp: (^\s*auth\s+)([\w\[].*\b)(\s+pam_faillock.so preauth.*)(deny)=[0-9]+(.*)
        line: \1required\3\4={{ var_accounts_passwords_pam_faillock_deny }}\5
        state: present
      loop:
        - /etc/pam.d/system-auth
        - /etc/pam.d/password-auth
      when:
        - result_pam_faillock_deny_parameter_is_present.found > 0

    - name: Lock Accounts After Failed Password Attempts - Ensure the desired value
        for pam_faillock.so authfail deny parameter in auth section
      ansible.builtin.lineinfile:
        path: '{{ item }}'
        backrefs: true
        regexp: (^\s*auth\s+)([\w\[].*\b)(\s+pam_faillock.so authfail.*)(deny)=[0-9]+(.*)
        line: \1required\3\4={{ var_accounts_passwords_pam_faillock_deny }}\5
        state: present
      loop:
        - /etc/pam.d/system-auth
        - /etc/pam.d/password-auth
      when:
        - result_pam_faillock_deny_parameter_is_present.found > 0
  when:
    - '"pam" in ansible_facts.packages'
    - not result_faillock_conf_check.stat.exists
  tags:
    - CJIS-5.5.3
    - NIST-800-171-3.1.8
    - NIST-800-53-AC-7(a)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-8.1.6
    - accounts_passwords_pam_faillock_deny
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

No more than one pam_unix.so is expected in auth section of system-auth  oval:ssg-test_accounts_passwords_pam_faillock_deny_system_pam_unix_auth:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_deny_system_pam_unix_auth:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*auth\N+pam_unix\.so^/etc/pam.d/system-auth$1

No more than one pam_unix.so is expected in auth section of password-auth  oval:ssg-test_accounts_passwords_pam_faillock_deny_password_pam_unix_auth:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_deny_password_pam_unix_auth:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*auth\N+pam_unix\.so^/etc/pam.d/password-auth$1

One and only one occurrence is expected in auth section of system-auth  oval:ssg-test_accounts_passwords_pam_faillock_deny_system_pam_faillock_auth:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_deny_system_pam_faillock_auth:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*auth[\s]+(required|\[(?=.*?\bsuccess=ok\b)(?=.*?\bnew_authtok_reqd=ok\b)(?=.*?\bignore=ignore\b)(?=.*?\bdefault=bad\b).*\])[\s]+pam_faillock\.so[\s\w\d=]+preauth[\s\S]*^[\s]*auth[\s]+(sufficient|\[(?=.*\bsuccess=done\b)(?=.*?\bnew_authtok_reqd=done\b)(?=.*?\bdefault=ignore\b).*\])[\s]+pam_unix\.so[\s\S]*^[\s]*auth[\s]+(required|\[(?=.*?\bsuccess=ok\b)(?=.*?\bnew_authtok_reqd=ok\b)(?=.*?\bignore=ignore\b)(?=.*?\bdefault=bad\b).*\])[\s]+pam_faillock\.so[\s\w\d=]+authfail^/etc/pam.d/system-auth$1

One and only one occurrence is expected in auth section of system-auth  oval:ssg-test_accounts_passwords_pam_faillock_deny_system_pam_faillock_account:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_deny_system_pam_faillock_account:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*account[\s]+(required|\[(?=.*?\bsuccess=ok\b)(?=.*?\bnew_authtok_reqd=ok\b)(?=.*?\bignore=ignore\b)(?=.*?\bdefault=bad\b).*\])[\s]+pam_faillock\.so[\s\S]*^[\s]*account[\s]+(required|\[(?=.*?\bsuccess=ok\b)(?=.*?\bnew_authtok_reqd=ok\b)(?=.*?\bignore=ignore\b)(?=.*?\bdefault=bad\b).*\])[\s]+pam_unix\.so^/etc/pam.d/system-auth$1

One and only one occurrence is expected in auth section of password-auth  oval:ssg-test_accounts_passwords_pam_faillock_deny_password_pam_faillock_auth:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_deny_password_pam_faillock_auth:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*auth[\s]+(required|\[(?=.*?\bsuccess=ok\b)(?=.*?\bnew_authtok_reqd=ok\b)(?=.*?\bignore=ignore\b)(?=.*?\bdefault=bad\b).*\])[\s]+pam_faillock\.so[\s\w\d=]+preauth[\s\S]*^[\s]*auth[\s]+(sufficient|\[(?=.*\bsuccess=done\b)(?=.*?\bnew_authtok_reqd=done\b)(?=.*?\bdefault=ignore\b).*\])[\s]+pam_unix\.so[\s\S]*^[\s]*auth[\s]+(required|\[(?=.*?\bsuccess=ok\b)(?=.*?\bnew_authtok_reqd=ok\b)(?=.*?\bignore=ignore\b)(?=.*?\bdefault=bad\b).*\])[\s]+pam_faillock\.so[\s\w\d=]+authfail^/etc/pam.d/password-auth$1

One and only one occurrence is expected in auth section of password-auth  oval:ssg-test_accounts_passwords_pam_faillock_deny_password_pam_faillock_account:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_deny_password_pam_faillock_account:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*account[\s]+(required|\[(?=.*?\bsuccess=ok\b)(?=.*?\bnew_authtok_reqd=ok\b)(?=.*?\bignore=ignore\b)(?=.*?\bdefault=bad\b).*\])[\s]+pam_faillock\.so[\s\S]*^[\s]*account[\s]+(required|\[(?=.*?\bsuccess=ok\b)(?=.*?\bnew_authtok_reqd=ok\b)(?=.*?\bignore=ignore\b)(?=.*?\bdefault=bad\b).*\])[\s]+pam_unix\.so^/etc/pam.d/password-auth$1

Check the expected deny value in system-auth  oval:ssg-test_accounts_passwords_pam_faillock_deny_parameter_pamd_system:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_deny_parameter_pamd_system:obj:1 of type textfilecontent54_object
FilepathPatternInstance
3
^[\s]*auth[\s]+.+[\s]+pam_faillock.so[\s]+[^\n]*deny=([0-9]+)
^/etc/pam.d/system-auth$1

Check the expected deny value in password-auth  oval:ssg-test_accounts_passwords_pam_faillock_deny_parameter_pamd_password:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_deny_parameter_pamd_password:obj:1 of type textfilecontent54_object
FilepathPatternInstance
3
^[\s]*auth[\s]+.+[\s]+pam_faillock.so[\s]+[^\n]*deny=([0-9]+)
^/etc/pam.d/password-auth$1

Check the absence of deny parameter in /etc/security/faillock.conf  oval:ssg-test_accounts_passwords_pam_faillock_deny_parameter_no_faillock_conf:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_deny_parameter_faillock_conf:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*deny[\s]*=[\s]*([0-9]+)^/etc/security/faillock.conf$1

Check the absence of deny parameter in system-auth  oval:ssg-test_accounts_passwords_pam_faillock_deny_parameter_no_pamd_system:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_deny_parameter_pamd_system:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*auth[\s]+.+[\s]+pam_faillock.so[\s]+[^\n]*deny=([0-9]+)^/etc/pam.d/system-auth$1

Check the absence of deny parameter in password-auth  oval:ssg-test_accounts_passwords_pam_faillock_deny_parameter_no_pamd_password:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_deny_parameter_pamd_password:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*auth[\s]+.+[\s]+pam_faillock.so[\s]+[^\n]*deny=([0-9]+)^/etc/pam.d/password-auth$1

Check the expected deny value in in /etc/security/faillock.conf  oval:ssg-test_accounts_passwords_pam_faillock_deny_parameter_faillock_conf:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_deny_parameter_faillock_conf:obj:1 of type textfilecontent54_object
FilepathPatternInstance
3
^[\s]*deny[\s]*=[\s]*([0-9]+)
^/etc/security/faillock.conf$1
Configure the root Account for Failed Password Attemptsxccdf_org.ssgproject.content_rule_accounts_passwords_pam_faillock_deny_root medium

Configure the root Account for Failed Password Attempts

Rule IDxccdf_org.ssgproject.content_rule_accounts_passwords_pam_faillock_deny_root
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-accounts_passwords_pam_faillock_deny_root:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  BP28(R18), 1, 12, 15, 16, DSS05.04, DSS05.10, DSS06.10, CCI-002238, CCI-000044, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, SR 1.1, SR 1.10, SR 1.2, SR 1.5, SR 1.7, SR 1.8, SR 1.9, 0421, 0422, 0431, 0974, 1173, 1401, 1504, 1505, 1546, 1557, 1558, 1559, 1560, 1561, A.18.1.4, A.9.2.1, A.9.2.4, A.9.3.1, A.9.4.2, A.9.4.3, CM-6(a), AC-7(b), IA-5(c), PR.AC-7, FMT_MOF_EXT.1, SRG-OS-000329-GPOS-00128, SRG-OS-000021-GPOS-00005

Description
This rule configures the system to lock out the root account after a number of incorrect login attempts using pam_faillock.so. pam_faillock.so module requires multiple entries in pam files. These entries must be carefully defined to work as expected. In order to avoid any errors when manually editing these files, it is recommended to use the appropriate tools, such as authselect or authconfig, depending on the OS version.
Rationale
By limiting the number of failed logon attempts, the risk of unauthorized system access via user password guessing, also known as brute-forcing, is reduced. Limits are imposed by locking the account.
Warnings
warning  If the system relies on authselect tool to manage PAM settings, the remediation will also use authselect tool. However, if any manual modification was made in PAM files, the authselect integrity check will fail and the remediation will be aborted in order to preserve intentional changes. In this case, an informative message will be shown in the remediation report. If the system supports the /etc/security/faillock.conf file, the pam_faillock parameters should be defined in faillock.conf file.

# Remediation is applicable only in certain platforms
if rpm --quiet -q pam; then

if [ -f /usr/bin/authselect ]; then
    if authselect check; then
    authselect enable-feature with-faillock
    authselect apply-changes
else
    echo "
authselect integrity check failed. Remediation aborted!
This remediation could not be applied because an authselect profile was not selected or the selected profile is not intact.
It is not recommended to manually edit the PAM files when authselect tool is available.
In cases where the default authselect profile does not cover a specific demand, a custom authselect profile is recommended."
    false
fi
else
    AUTH_FILES=("/etc/pam.d/system-auth" "/etc/pam.d/password-auth")
for pam_file in "${AUTH_FILES[@]}"
do
    if ! grep -qE '^\s*auth\s+required\s+pam_faillock\.so\s+(preauth silent|authfail).*$' "$pam_file" ; then
        sed -i --follow-symlinks '/^auth.*sufficient.*pam_unix.so.*/i auth        required      pam_faillock.so preauth silent' "$pam_file"
        sed -i --follow-symlinks '/^auth.*sufficient.*pam_unix.so.*/a auth        required      pam_faillock.so authfail' "$pam_file"
        sed -i --follow-symlinks '/^account.*required.*pam_unix.so.*/i account     required      pam_faillock.so' "$pam_file"
    fi
    sed -Ei 's/(auth.*)(\[default=die\])(.*pam_faillock.so)/\1required     \3/g' "$pam_file"
done
fi
FAILLOCK_CONF="/etc/security/faillock.conf"
if [ -f $FAILLOCK_CONF ]; then
    regex="^\s*even_deny_root"
    line="even_deny_root"
    if ! grep -q $regex $FAILLOCK_CONF; then
        echo $line >> $FAILLOCK_CONF
    fi
else
    AUTH_FILES=("/etc/pam.d/system-auth" "/etc/pam.d/password-auth")
    for pam_file in "${AUTH_FILES[@]}"
    do
        if ! grep -qE '^\s*auth.*pam_faillock.so (preauth|authfail).*even_deny_root' "$pam_file"; then
            sed -i --follow-symlinks '/^auth.*required.*pam_faillock.so.*preauth.*silent.*/ s/$/ even_deny_root/' "$pam_file"
            sed -i --follow-symlinks '/^auth.*required.*pam_faillock.so.*authfail.*/ s/$/ even_deny_root/' "$pam_file"
        fi
    done
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AC-7(b)
    - NIST-800-53-CM-6(a)
    - NIST-800-53-IA-5(c)
    - accounts_passwords_pam_faillock_deny_root
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Configure the root Account for Failed Password Attempts - Check if system
    relies on authselect tool
  ansible.builtin.stat:
    path: /usr/bin/authselect
  register: result_authselect_present
  when: '"pam" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-7(b)
    - NIST-800-53-CM-6(a)
    - NIST-800-53-IA-5(c)
    - accounts_passwords_pam_faillock_deny_root
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Configure the root Account for Failed Password Attempts - Remediation where
    authselect tool is present
  block:

    - name: Configure the root Account for Failed Password Attempts - Check integrity
        of authselect current profile
      ansible.builtin.command:
        cmd: authselect check
      register: result_authselect_check_cmd
      changed_when: false
      ignore_errors: true

    - name: Configure the root Account for Failed Password Attempts - Informative
        message based on the authselect integrity check result
      ansible.builtin.assert:
        that:
          - result_authselect_check_cmd is success
        fail_msg:
          - authselect integrity check failed. Remediation aborted!
          - This remediation could not be applied because an authselect profile was
            not selected or the selected profile is not intact.
          - It is not recommended to manually edit the PAM files when authselect tool
            is available.
          - In cases where the default authselect profile does not cover a specific
            demand, a custom authselect profile is recommended.
        success_msg:
          - authselect integrity check passed

    - name: Configure the root Account for Failed Password Attempts - Get authselect
        current features
      ansible.builtin.shell:
        cmd: authselect current | tail -n+3 | awk '{ print $2 }'
      register: result_authselect_features
      changed_when: false
      when:
        - result_authselect_check_cmd is success

    - name: Configure the root Account for Failed Password Attempts - Ensure with-faillock
        feature is enabled using authselect tool
      ansible.builtin.command:
        cmd: authselect enable-feature with-faillock
      register: result_authselect_cmd
      when:
        - result_authselect_check_cmd is success
        - result_authselect_features.stdout is not search("with-faillock")
  when:
    - '"pam" in ansible_facts.packages'
    - result_authselect_present.stat.exists
  tags:
    - NIST-800-53-AC-7(b)
    - NIST-800-53-CM-6(a)
    - NIST-800-53-IA-5(c)
    - accounts_passwords_pam_faillock_deny_root
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Configure the root Account for Failed Password Attempts - Remediation where
    authselect tool is not present
  block:

    - name: Configure the root Account for Failed Password Attempts - Check if pam_faillock.so
        is already enabled
      ansible.builtin.lineinfile:
        path: /etc/pam.d/system-auth
        regexp: .*auth.*pam_faillock.so (preauth|authfail)
        state: absent
      check_mode: true
      changed_when: false
      register: result_pam_faillock_is_enabled

    - name: Configure the root Account for Failed Password Attempts - Enable pam_faillock.so
        preauth editing PAM files
      ansible.builtin.lineinfile:
        path: '{{ item }}'
        line: auth        required      pam_faillock.so preauth
        insertbefore: ^auth.*sufficient.*pam_unix.so.*
        state: present
      loop:
        - /etc/pam.d/system-auth
        - /etc/pam.d/password-auth
      when:
        - result_pam_faillock_is_enabled.found == 0

    - name: Configure the root Account for Failed Password Attempts - Enable pam_faillock.so
        authfail editing PAM files
      ansible.builtin.lineinfile:
        path: '{{ item }}'
        line: auth        required      pam_faillock.so authfail
        insertafter: ^auth.*sufficient.*pam_unix.so.*
        state: present
      loop:
        - /etc/pam.d/system-auth
        - /etc/pam.d/password-auth
      when:
        - result_pam_faillock_is_enabled.found == 0

    - name: Configure the root Account for Failed Password Attempts - Enable pam_faillock.so
        account section editing PAM files
      ansible.builtin.lineinfile:
        path: '{{ item }}'
        line: account     required      pam_faillock.so
        insertbefore: ^account.*required.*pam_unix.so.*
        state: present
      loop:
        - /etc/pam.d/system-auth
        - /etc/pam.d/password-auth
      when:
        - result_pam_faillock_is_enabled.found == 0
  when:
    - '"pam" in ansible_facts.packages'
    - not result_authselect_present.stat.exists
  tags:
    - NIST-800-53-AC-7(b)
    - NIST-800-53-CM-6(a)
    - NIST-800-53-IA-5(c)
    - accounts_passwords_pam_faillock_deny_root
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Configure the root Account for Failed Password Attempts - Check the presence
    of /etc/security/faillock.conf file
  ansible.builtin.stat:
    path: /etc/security/faillock.conf
  register: result_faillock_conf_check
  when: '"pam" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-7(b)
    - NIST-800-53-CM-6(a)
    - NIST-800-53-IA-5(c)
    - accounts_passwords_pam_faillock_deny_root
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Configure the root Account for Failed Password Attempts - Ensure the pam_faillock.so
    even_deny_root parameter in /etc/security/faillock.conf
  ansible.builtin.lineinfile:
    path: /etc/security/faillock.conf
    regexp: ^\s*even_deny_root
    line: even_deny_root
    state: present
  when:
    - '"pam" in ansible_facts.packages'
    - result_faillock_conf_check.stat.exists
  tags:
    - NIST-800-53-AC-7(b)
    - NIST-800-53-CM-6(a)
    - NIST-800-53-IA-5(c)
    - accounts_passwords_pam_faillock_deny_root
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Configure the root Account for Failed Password Attempts - Ensure the pam_faillock.so
    even_deny_root parameter in PAM files
  block:

    - name: Configure the root Account for Failed Password Attempts - Check if pam_faillock.so
        even_deny_root parameter is already enabled in pam files
      ansible.builtin.lineinfile:
        path: /etc/pam.d/system-auth
        regexp: .*auth.*pam_faillock.so (preauth|authfail).*even_deny_root
        state: absent
      check_mode: true
      changed_when: false
      register: result_pam_faillock_even_deny_root_parameter_is_present

    - name: Configure the root Account for Failed Password Attempts - Ensure the inclusion
        of pam_faillock.so preauth even_deny_root parameter in auth section
      ansible.builtin.lineinfile:
        path: '{{ item }}'
        backrefs: true
        regexp: (^\s*auth\s+)([\w\[].*\b)(\s+pam_faillock.so preauth.*)
        line: \1required\3 even_deny_root
        state: present
      loop:
        - /etc/pam.d/system-auth
        - /etc/pam.d/password-auth
      when:
        - result_pam_faillock_even_deny_root_parameter_is_present.found == 0

    - name: Configure the root Account for Failed Password Attempts - Ensure the inclusion
        of pam_faillock.so authfail even_deny_root parameter in auth section
      ansible.builtin.lineinfile:
        path: '{{ item }}'
        backrefs: true
        regexp: (^\s*auth\s+)([\w\[].*\b)(\s+pam_faillock.so authfail.*)
        line: \1required\3 even_deny_root
        state: present
      loop:
        - /etc/pam.d/system-auth
        - /etc/pam.d/password-auth
      when:
        - result_pam_faillock_even_deny_root_parameter_is_present.found == 0
  when:
    - '"pam" in ansible_facts.packages'
    - not result_faillock_conf_check.stat.exists
  tags:
    - NIST-800-53-AC-7(b)
    - NIST-800-53-CM-6(a)
    - NIST-800-53-IA-5(c)
    - accounts_passwords_pam_faillock_deny_root
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

No more than one pam_unix.so is expected in auth section of system-auth  oval:ssg-test_accounts_passwords_pam_faillock_deny_root_system_pam_unix_auth:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_deny_root_system_pam_unix_auth:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*auth\N+pam_unix\.so^/etc/pam.d/system-auth$1

No more than one pam_unix.so is expected in auth section of password-auth  oval:ssg-test_accounts_passwords_pam_faillock_deny_root_password_pam_unix_auth:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_deny_root_password_pam_unix_auth:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*auth\N+pam_unix\.so^/etc/pam.d/password-auth$1

One and only one pattern occurrence is expected in auth section of system-auth  oval:ssg-test_accounts_passwords_pam_faillock_deny_root_system_pam_faillock_auth:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_deny_root_system_pam_faillock_auth:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*auth[\s]+(required|\[(?=.*?\bsuccess=ok\b)(?=.*?\bnew_authtok_reqd=ok\b)(?=.*?\bignore=ignore\b)(?=.*?\bdefault=bad\b).*\])[\s]+pam_faillock\.so[\s\w\d=]+preauth[\s\S]*^[\s]*auth[\s]+(sufficient|\[(?=.*\bsuccess=done\b)(?=.*?\bnew_authtok_reqd=done\b)(?=.*?\bdefault=ignore\b).*\])[\s]+pam_unix\.so[\s\S]*^[\s]*auth[\s]+(required|\[(?=.*?\bsuccess=ok\b)(?=.*?\bnew_authtok_reqd=ok\b)(?=.*?\bignore=ignore\b)(?=.*?\bdefault=bad\b).*\])[\s]+pam_faillock\.so[\s\w\d=]+authfail^/etc/pam.d/system-auth$1

One and only one pattern occurrence is expected in account section of system-auth  oval:ssg-test_accounts_passwords_pam_faillock_deny_root_system_pam_faillock_account:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_deny_root_system_pam_faillock_account:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*account[\s]+(required|\[(?=.*?\bsuccess=ok\b)(?=.*?\bnew_authtok_reqd=ok\b)(?=.*?\bignore=ignore\b)(?=.*?\bdefault=bad\b).*\])[\s]+pam_faillock\.so[\s\S]*^[\s]*account[\s]+(required|\[(?=.*?\bsuccess=ok\b)(?=.*?\bnew_authtok_reqd=ok\b)(?=.*?\bignore=ignore\b)(?=.*?\bdefault=bad\b).*\])[\s]+pam_unix\.so^/etc/pam.d/system-auth$1

One and only one pattern occurrence is expected in auth section of system-auth  oval:ssg-test_accounts_passwords_pam_faillock_deny_root_password_pam_faillock_auth:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_deny_root_password_pam_faillock_auth:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*auth[\s]+(required|\[(?=.*?\bsuccess=ok\b)(?=.*?\bnew_authtok_reqd=ok\b)(?=.*?\bignore=ignore\b)(?=.*?\bdefault=bad\b).*\])[\s]+pam_faillock\.so[\s\w\d=]+preauth[\s\S]*^[\s]*auth[\s]+(sufficient|\[(?=.*\bsuccess=done\b)(?=.*?\bnew_authtok_reqd=done\b)(?=.*?\bdefault=ignore\b).*\])[\s]+pam_unix\.so[\s\S]*^[\s]*auth[\s]+(required|\[(?=.*?\bsuccess=ok\b)(?=.*?\bnew_authtok_reqd=ok\b)(?=.*?\bignore=ignore\b)(?=.*?\bdefault=bad\b).*\])[\s]+pam_faillock\.so[\s\w\d=]+authfail^/etc/pam.d/password-auth$1

One and only one pattern occurrence is expected in account section of password-auth  oval:ssg-test_accounts_passwords_pam_faillock_deny_root_password_pam_faillock_account:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_deny_root_password_pam_faillock_account:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*account[\s]+(required|\[(?=.*?\bsuccess=ok\b)(?=.*?\bnew_authtok_reqd=ok\b)(?=.*?\bignore=ignore\b)(?=.*?\bdefault=bad\b).*\])[\s]+pam_faillock\.so[\s\S]*^[\s]*account[\s]+(required|\[(?=.*?\bsuccess=ok\b)(?=.*?\bnew_authtok_reqd=ok\b)(?=.*?\bignore=ignore\b)(?=.*?\bdefault=bad\b).*\])[\s]+pam_unix\.so^/etc/pam.d/password-auth$1

Check the expected even_deny_root parameter in system-auth  oval:ssg-test_accounts_passwords_pam_faillock_deny_root_parameter_pamd_system:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_deny_root_parameter_pamd_system:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*auth[\s]+.+[\s]+pam_faillock.so[\s]+[^\n]*even_deny_root^/etc/pam.d/system-auth$1

Check the expected even_deny_root parameter in password-auth  oval:ssg-test_accounts_passwords_pam_faillock_deny_root_parameter_pamd_password:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_deny_root_parameter_pamd_password:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*auth[\s]+.+[\s]+pam_faillock.so[\s]+[^\n]*even_deny_root^/etc/pam.d/password-auth$1

Check the absence of even_deny_root parameter in /etc/security/faillock.conf  oval:ssg-test_accounts_passwords_pam_faillock_deny_root_parameter_no_faillock_conf:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_deny_root_parameter_faillock_conf:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*even_deny_root^/etc/security/faillock.conf$1

Check the absence of even_deny_root parameter in system-auth  oval:ssg-test_accounts_passwords_pam_faillock_deny_root_parameter_no_pamd_system:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_deny_root_parameter_pamd_system:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*auth[\s]+.+[\s]+pam_faillock.so[\s]+[^\n]*even_deny_root^/etc/pam.d/system-auth$1

Check the absence of even_deny_root parameter in password-auth  oval:ssg-test_accounts_passwords_pam_faillock_deny_root_parameter_no_pamd_password:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_deny_root_parameter_pamd_password:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*auth[\s]+.+[\s]+pam_faillock.so[\s]+[^\n]*even_deny_root^/etc/pam.d/password-auth$1

Check the expected even_deny_root parameter in /etc/security/faillock.conf  oval:ssg-test_accounts_passwords_pam_faillock_deny_root_parameter_faillock_conf:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_deny_root_parameter_faillock_conf:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*even_deny_root^/etc/security/faillock.conf$1
Set Interval For Counting Failed Password Attemptsxccdf_org.ssgproject.content_rule_accounts_passwords_pam_faillock_interval medium

Set Interval For Counting Failed Password Attempts

Rule IDxccdf_org.ssgproject.content_rule_accounts_passwords_pam_faillock_interval
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-accounts_passwords_pam_faillock_interval:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  BP28(R18), 1, 12, 15, 16, DSS05.04, DSS05.10, DSS06.10, CCI-000044, CCI-002236, CCI-002237, CCI-002238, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, SR 1.1, SR 1.10, SR 1.2, SR 1.5, SR 1.7, SR 1.8, SR 1.9, 0421, 0422, 0431, 0974, 1173, 1401, 1504, 1505, 1546, 1557, 1558, 1559, 1560, 1561, A.18.1.4, A.9.2.1, A.9.2.4, A.9.3.1, A.9.4.2, A.9.4.3, CM-6(a), AC-7(a), PR.AC-7, FIA_AFL.1, SRG-OS-000329-GPOS-00128, SRG-OS-000021-GPOS-00005, SRG-OS-000021-VMM-000050

Description
Utilizing pam_faillock.so, the fail_interval directive configures the system to lock out an account after a number of incorrect login attempts within a specified time period. First make sure the feature is enabled using the following command:

  • authselect enable-feature with-faillock

Then edit the /etc/security/faillock.conf file as follows:

  • add, uncomment or edit the following line:
    fail_interval = 900
  • add or uncomment the following line:
    silent
Rationale
By limiting the number of failed logon attempts the risk of unauthorized system access via user password guessing, otherwise known as brute-forcing, is reduced. Limits are imposed by locking the account.
Warnings
warning  If the system relies on authselect tool to manage PAM settings, the remediation will also use authselect tool. However, if any manual modification was made in PAM files, the authselect integrity check will fail and the remediation will be aborted in order to preserve intentional changes. In this case, an informative message will be shown in the remediation report. If the system supports the /etc/security/faillock.conf file, the pam_faillock parameters should be defined in faillock.conf file.

# Remediation is applicable only in certain platforms
if rpm --quiet -q pam; then

var_accounts_passwords_pam_faillock_fail_interval='900'


if [ -f /usr/bin/authselect ]; then
    if authselect check; then
    authselect enable-feature with-faillock
    authselect apply-changes
else
    echo "
authselect integrity check failed. Remediation aborted!
This remediation could not be applied because an authselect profile was not selected or the selected profile is not intact.
It is not recommended to manually edit the PAM files when authselect tool is available.
In cases where the default authselect profile does not cover a specific demand, a custom authselect profile is recommended."
    false
fi
else
    AUTH_FILES=("/etc/pam.d/system-auth" "/etc/pam.d/password-auth")
for pam_file in "${AUTH_FILES[@]}"
do
    if ! grep -qE '^\s*auth\s+required\s+pam_faillock\.so\s+(preauth silent|authfail).*$' "$pam_file" ; then
        sed -i --follow-symlinks '/^auth.*sufficient.*pam_unix.so.*/i auth        required      pam_faillock.so preauth silent' "$pam_file"
        sed -i --follow-symlinks '/^auth.*sufficient.*pam_unix.so.*/a auth        required      pam_faillock.so authfail' "$pam_file"
        sed -i --follow-symlinks '/^account.*required.*pam_unix.so.*/i account     required      pam_faillock.so' "$pam_file"
    fi
    sed -Ei 's/(auth.*)(\[default=die\])(.*pam_faillock.so)/\1required     \3/g' "$pam_file"
done
fi
FAILLOCK_CONF="/etc/security/faillock.conf"
if [ -f $FAILLOCK_CONF ]; then
    regex="^\s*fail_interval\s*="
    line="fail_interval = $var_accounts_passwords_pam_faillock_fail_interval"
    if ! grep -q $regex $FAILLOCK_CONF; then
        echo $line >> $FAILLOCK_CONF
    else
        sed -i --follow-symlinks 's/^\s*\(fail_interval\s*=\s*\)\([0-9]\+\)/\1'"$var_accounts_passwords_pam_faillock_fail_interval"'/g' $FAILLOCK_CONF
    fi
else
    AUTH_FILES=("/etc/pam.d/system-auth" "/etc/pam.d/password-auth")
    for pam_file in "${AUTH_FILES[@]}"
    do
        if ! grep -qE '^\s*auth.*pam_faillock.so (preauth|authfail).*fail_interval' "$pam_file"; then
            sed -i --follow-symlinks '/^auth.*required.*pam_faillock.so.*preauth.*silent.*/ s/$/ fail_interval='"$var_accounts_passwords_pam_faillock_fail_interval"'/' "$pam_file"
            sed -i --follow-symlinks '/^auth.*required.*pam_faillock.so.*authfail.*/ s/$/ fail_interval='"$var_accounts_passwords_pam_faillock_fail_interval"'/' "$pam_file"
        else
            sed -i --follow-symlinks 's/\(^auth.*required.*pam_faillock.so.*preauth.*silent.*\)\('"fail_interval"'=\)[0-9]\+\(.*\)/\1\2'"$var_accounts_passwords_pam_faillock_fail_interval"'\3/' "$pam_file"
            sed -i --follow-symlinks 's/\(^auth.*required.*pam_faillock.so.*authfail.*\)\('"fail_interval"'=\)[0-9]\+\(.*\)/\1\2'"$var_accounts_passwords_pam_faillock_fail_interval"'\3/' "$pam_file"
        fi
    done
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AC-7(a)
    - NIST-800-53-CM-6(a)
    - accounts_passwords_pam_faillock_interval
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Set Interval For Counting Failed Password Attempts - Check if system relies
    on authselect tool
  ansible.builtin.stat:
    path: /usr/bin/authselect
  register: result_authselect_present
  when: '"pam" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-7(a)
    - NIST-800-53-CM-6(a)
    - accounts_passwords_pam_faillock_interval
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Set Interval For Counting Failed Password Attempts - Remediation where authselect
    tool is present
  block:

    - name: Set Interval For Counting Failed Password Attempts - Check integrity of
        authselect current profile
      ansible.builtin.command:
        cmd: authselect check
      register: result_authselect_check_cmd
      changed_when: false
      ignore_errors: true

    - name: Set Interval For Counting Failed Password Attempts - Informative message
        based on the authselect integrity check result
      ansible.builtin.assert:
        that:
          - result_authselect_check_cmd is success
        fail_msg:
          - authselect integrity check failed. Remediation aborted!
          - This remediation could not be applied because an authselect profile was
            not selected or the selected profile is not intact.
          - It is not recommended to manually edit the PAM files when authselect tool
            is available.
          - In cases where the default authselect profile does not cover a specific
            demand, a custom authselect profile is recommended.
        success_msg:
          - authselect integrity check passed

    - name: Set Interval For Counting Failed Password Attempts - Get authselect current
        features
      ansible.builtin.shell:
        cmd: authselect current | tail -n+3 | awk '{ print $2 }'
      register: result_authselect_features
      changed_when: false
      when:
        - result_authselect_check_cmd is success

    - name: Set Interval For Counting Failed Password Attempts - Ensure with-faillock
        feature is enabled using authselect tool
      ansible.builtin.command:
        cmd: authselect enable-feature with-faillock
      register: result_authselect_cmd
      when:
        - result_authselect_check_cmd is success
        - result_authselect_features.stdout is not search("with-faillock")
  when:
    - '"pam" in ansible_facts.packages'
    - result_authselect_present.stat.exists
  tags:
    - NIST-800-53-AC-7(a)
    - NIST-800-53-CM-6(a)
    - accounts_passwords_pam_faillock_interval
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Set Interval For Counting Failed Password Attempts - Remediation where authselect
    tool is not present
  block:

    - name: Set Interval For Counting Failed Password Attempts - Check if pam_faillock.so
        is already enabled
      ansible.builtin.lineinfile:
        path: /etc/pam.d/system-auth
        regexp: .*auth.*pam_faillock.so (preauth|authfail)
        state: absent
      check_mode: true
      changed_when: false
      register: result_pam_faillock_is_enabled

    - name: Set Interval For Counting Failed Password Attempts - Enable pam_faillock.so
        preauth editing PAM files
      ansible.builtin.lineinfile:
        path: '{{ item }}'
        line: auth        required      pam_faillock.so preauth
        insertbefore: ^auth.*sufficient.*pam_unix.so.*
        state: present
      loop:
        - /etc/pam.d/system-auth
        - /etc/pam.d/password-auth
      when:
        - result_pam_faillock_is_enabled.found == 0

    - name: Set Interval For Counting Failed Password Attempts - Enable pam_faillock.so
        authfail editing PAM files
      ansible.builtin.lineinfile:
        path: '{{ item }}'
        line: auth        required      pam_faillock.so authfail
        insertafter: ^auth.*sufficient.*pam_unix.so.*
        state: present
      loop:
        - /etc/pam.d/system-auth
        - /etc/pam.d/password-auth
      when:
        - result_pam_faillock_is_enabled.found == 0

    - name: Set Interval For Counting Failed Password Attempts - Enable pam_faillock.so
        account section editing PAM files
      ansible.builtin.lineinfile:
        path: '{{ item }}'
        line: account     required      pam_faillock.so
        insertbefore: ^account.*required.*pam_unix.so.*
        state: present
      loop:
        - /etc/pam.d/system-auth
        - /etc/pam.d/password-auth
      when:
        - result_pam_faillock_is_enabled.found == 0
  when:
    - '"pam" in ansible_facts.packages'
    - not result_authselect_present.stat.exists
  tags:
    - NIST-800-53-AC-7(a)
    - NIST-800-53-CM-6(a)
    - accounts_passwords_pam_faillock_interval
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
- name: XCCDF Value var_accounts_passwords_pam_faillock_fail_interval # promote to variable
  set_fact:
    var_accounts_passwords_pam_faillock_fail_interval: !!str 900
  tags:
    - always

- name: Set Interval For Counting Failed Password Attempts - Check the presence of
    /etc/security/faillock.conf file
  ansible.builtin.stat:
    path: /etc/security/faillock.conf
  register: result_faillock_conf_check
  when: '"pam" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-7(a)
    - NIST-800-53-CM-6(a)
    - accounts_passwords_pam_faillock_interval
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Set Interval For Counting Failed Password Attempts - Ensure the pam_faillock.so
    fail_interval parameter in /etc/security/faillock.conf
  ansible.builtin.lineinfile:
    path: /etc/security/faillock.conf
    regexp: ^\s*fail_interval\s*=
    line: fail_interval = {{ var_accounts_passwords_pam_faillock_fail_interval }}
    state: present
  when:
    - '"pam" in ansible_facts.packages'
    - result_faillock_conf_check.stat.exists
  tags:
    - NIST-800-53-AC-7(a)
    - NIST-800-53-CM-6(a)
    - accounts_passwords_pam_faillock_interval
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Set Interval For Counting Failed Password Attempts - Ensure the pam_faillock.so
    fail_interval parameter in PAM files
  block:

    - name: Set Interval For Counting Failed Password Attempts - Check if pam_faillock.so
        fail_interval parameter is already enabled in pam files
      ansible.builtin.lineinfile:
        path: /etc/pam.d/system-auth
        regexp: .*auth.*pam_faillock.so (preauth|authfail).*fail_interval
        state: absent
      check_mode: true
      changed_when: false
      register: result_pam_faillock_fail_interval_parameter_is_present

    - name: Set Interval For Counting Failed Password Attempts - Ensure the inclusion
        of pam_faillock.so preauth fail_interval parameter in auth section
      ansible.builtin.lineinfile:
        path: '{{ item }}'
        backrefs: true
        regexp: (^\s*auth\s+)([\w\[].*\b)(\s+pam_faillock.so preauth.*)
        line: \1required\3 fail_interval={{ var_accounts_passwords_pam_faillock_fail_interval
          }}
        state: present
      loop:
        - /etc/pam.d/system-auth
        - /etc/pam.d/password-auth
      when:
        - result_pam_faillock_fail_interval_parameter_is_present.found == 0

    - name: Set Interval For Counting Failed Password Attempts - Ensure the inclusion
        of pam_faillock.so authfail fail_interval parameter in auth section
      ansible.builtin.lineinfile:
        path: '{{ item }}'
        backrefs: true
        regexp: (^\s*auth\s+)([\w\[].*\b)(\s+pam_faillock.so authfail.*)
        line: \1required\3 fail_interval={{ var_accounts_passwords_pam_faillock_fail_interval
          }}
        state: present
      loop:
        - /etc/pam.d/system-auth
        - /etc/pam.d/password-auth
      when:
        - result_pam_faillock_fail_interval_parameter_is_present.found == 0

    - name: Set Interval For Counting Failed Password Attempts - Ensure the desired
        value for pam_faillock.so preauth fail_interval parameter in auth section
      ansible.builtin.lineinfile:
        path: '{{ item }}'
        backrefs: true
        regexp: (^\s*auth\s+)([\w\[].*\b)(\s+pam_faillock.so preauth.*)(fail_interval)=[0-9]+(.*)
        line: \1required\3\4={{ var_accounts_passwords_pam_faillock_fail_interval
          }}\5
        state: present
      loop:
        - /etc/pam.d/system-auth
        - /etc/pam.d/password-auth
      when:
        - result_pam_faillock_fail_interval_parameter_is_present.found > 0

    - name: Set Interval For Counting Failed Password Attempts - Ensure the desired
        value for pam_faillock.so authfail fail_interval parameter in auth section
      ansible.builtin.lineinfile:
        path: '{{ item }}'
        backrefs: true
        regexp: (^\s*auth\s+)([\w\[].*\b)(\s+pam_faillock.so authfail.*)(fail_interval)=[0-9]+(.*)
        line: \1required\3\4={{ var_accounts_passwords_pam_faillock_fail_interval
          }}\5
        state: present
      loop:
        - /etc/pam.d/system-auth
        - /etc/pam.d/password-auth
      when:
        - result_pam_faillock_fail_interval_parameter_is_present.found > 0
  when:
    - '"pam" in ansible_facts.packages'
    - not result_faillock_conf_check.stat.exists
  tags:
    - NIST-800-53-AC-7(a)
    - NIST-800-53-CM-6(a)
    - accounts_passwords_pam_faillock_interval
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

No more than one pam_unix.so is expected in auth section of system-auth  oval:ssg-test_accounts_passwords_pam_faillock_interval_system_pam_unix_auth:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_interval_system_pam_unix_auth:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*auth\N+pam_unix\.so^/etc/pam.d/system-auth$1

No more than one pam_unix.so is expected in auth section of password-auth  oval:ssg-test_accounts_passwords_pam_faillock_interval_password_pam_unix_auth:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_interval_password_pam_unix_auth:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*auth\N+pam_unix\.so^/etc/pam.d/password-auth$1

One and only one occurrence is expected in auth section of system-auth  oval:ssg-test_accounts_passwords_pam_faillock_interval_system_pam_faillock_auth:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_interval_system_pam_faillock_auth:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*auth[\s]+(required|\[(?=.*?\bsuccess=ok\b)(?=.*?\bnew_authtok_reqd=ok\b)(?=.*?\bignore=ignore\b)(?=.*?\bdefault=bad\b).*\])[\s]+pam_faillock\.so[\s\w\d=]+preauth[\s\S]*^[\s]*auth[\s]+(sufficient|\[(?=.*\bsuccess=done\b)(?=.*?\bnew_authtok_reqd=done\b)(?=.*?\bdefault=ignore\b).*\])[\s]+pam_unix\.so[\s\S]*^[\s]*auth[\s]+(required|\[(?=.*?\bsuccess=ok\b)(?=.*?\bnew_authtok_reqd=ok\b)(?=.*?\bignore=ignore\b)(?=.*?\bdefault=bad\b).*\])[\s]+pam_faillock\.so[\s\w\d=]+authfail^/etc/pam.d/system-auth$1

One and only one occurrence is expected in auth section of system-auth  oval:ssg-test_accounts_passwords_pam_faillock_interval_system_pam_faillock_account:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_interval_system_pam_faillock_account:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*account[\s]+(required|\[(?=.*?\bsuccess=ok\b)(?=.*?\bnew_authtok_reqd=ok\b)(?=.*?\bignore=ignore\b)(?=.*?\bdefault=bad\b).*\])[\s]+pam_faillock\.so[\s\S]*^[\s]*account[\s]+(required|\[(?=.*?\bsuccess=ok\b)(?=.*?\bnew_authtok_reqd=ok\b)(?=.*?\bignore=ignore\b)(?=.*?\bdefault=bad\b).*\])[\s]+pam_unix\.so^/etc/pam.d/system-auth$1

One and only one occurrence is expected in auth section of password-auth  oval:ssg-test_accounts_passwords_pam_faillock_interval_password_pam_faillock_auth:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_interval_password_pam_faillock_auth:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*auth[\s]+(required|\[(?=.*?\bsuccess=ok\b)(?=.*?\bnew_authtok_reqd=ok\b)(?=.*?\bignore=ignore\b)(?=.*?\bdefault=bad\b).*\])[\s]+pam_faillock\.so[\s\w\d=]+preauth[\s\S]*^[\s]*auth[\s]+(sufficient|\[(?=.*\bsuccess=done\b)(?=.*?\bnew_authtok_reqd=done\b)(?=.*?\bdefault=ignore\b).*\])[\s]+pam_unix\.so[\s\S]*^[\s]*auth[\s]+(required|\[(?=.*?\bsuccess=ok\b)(?=.*?\bnew_authtok_reqd=ok\b)(?=.*?\bignore=ignore\b)(?=.*?\bdefault=bad\b).*\])[\s]+pam_faillock\.so[\s\w\d=]+authfail^/etc/pam.d/password-auth$1

One and only one occurrence is expected in auth section of password-auth  oval:ssg-test_accounts_passwords_pam_faillock_interval_password_pam_faillock_account:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_interval_password_pam_faillock_account:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*account[\s]+(required|\[(?=.*?\bsuccess=ok\b)(?=.*?\bnew_authtok_reqd=ok\b)(?=.*?\bignore=ignore\b)(?=.*?\bdefault=bad\b).*\])[\s]+pam_faillock\.so[\s\S]*^[\s]*account[\s]+(required|\[(?=.*?\bsuccess=ok\b)(?=.*?\bnew_authtok_reqd=ok\b)(?=.*?\bignore=ignore\b)(?=.*?\bdefault=bad\b).*\])[\s]+pam_unix\.so^/etc/pam.d/password-auth$1

Check the expected fail_interval value in system-auth  oval:ssg-test_accounts_passwords_pam_faillock_interval_parameter_pamd_system:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_interval_parameter_pamd_system:obj:1 of type textfilecontent54_object
FilepathPatternInstance
900
^[\s]*auth[\s]+.+[\s]+pam_faillock.so[\s]+[^\n]*fail_interval=([0-9]+)
^/etc/pam.d/system-auth$1

Check the expected fail_interval value in password-auth  oval:ssg-test_accounts_passwords_pam_faillock_interval_parameter_pamd_password:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_interval_parameter_pamd_password:obj:1 of type textfilecontent54_object
FilepathPatternInstance
900
^[\s]*auth[\s]+.+[\s]+pam_faillock.so[\s]+[^\n]*fail_interval=([0-9]+)
^/etc/pam.d/password-auth$1

Check the absence of fail_interval parameter in /etc/security/faillock.conf  oval:ssg-test_accounts_passwords_pam_faillock_interval_parameter_no_faillock_conf:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_interval_parameter_faillock_conf:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*fail_interval[\s]*=[\s]*([0-9]+)^/etc/security/faillock.conf$1

Check the absence of fail_interval parameter in system-auth  oval:ssg-test_accounts_passwords_pam_faillock_interval_parameter_no_pamd_system:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_interval_parameter_pamd_system:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*auth[\s]+.+[\s]+pam_faillock.so[\s]+[^\n]*fail_interval=([0-9]+)^/etc/pam.d/system-auth$1

Check the absence of fail_interval parameter in password-auth  oval:ssg-test_accounts_passwords_pam_faillock_interval_parameter_no_pamd_password:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_interval_parameter_pamd_password:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*auth[\s]+.+[\s]+pam_faillock.so[\s]+[^\n]*fail_interval=([0-9]+)^/etc/pam.d/password-auth$1

Check the expected fail_interval value in in /etc/security/faillock.conf  oval:ssg-test_accounts_passwords_pam_faillock_interval_parameter_faillock_conf:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_interval_parameter_faillock_conf:obj:1 of type textfilecontent54_object
FilepathPatternInstance
900
^[\s]*fail_interval[\s]*=[\s]*([0-9]+)
^/etc/security/faillock.conf$1
Set Lockout Time for Failed Password Attemptsxccdf_org.ssgproject.content_rule_accounts_passwords_pam_faillock_unlock_time medium

Set Lockout Time for Failed Password Attempts

Rule IDxccdf_org.ssgproject.content_rule_accounts_passwords_pam_faillock_unlock_time
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-accounts_passwords_pam_faillock_unlock_time:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  BP28(R18), 1, 12, 15, 16, 5.5.3, DSS05.04, DSS05.10, DSS06.10, 3.1.8, CCI-000044, CCI-002236, CCI-002237, CCI-002238, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, SR 1.1, SR 1.10, SR 1.2, SR 1.5, SR 1.7, SR 1.8, SR 1.9, 0421, 0422, 0431, 0974, 1173, 1401, 1504, 1505, 1546, 1557, 1558, 1559, 1560, 1561, A.18.1.4, A.9.2.1, A.9.2.4, A.9.3.1, A.9.4.2, A.9.4.3, CM-6(a), AC-7(b), PR.AC-7, FIA_AFL.1, Req-8.1.7, SRG-OS-000329-GPOS-00128, SRG-OS-000021-GPOS-00005, SRG-OS-000329-VMM-001180

Description
This rule configures the system to lock out accounts during a specified time period after a number of incorrect login attempts using pam_faillock.so. pam_faillock.so module requires multiple entries in pam files. These entries must be carefully defined to work as expected. In order to avoid any errors when manually editing these files, it is recommended to use the appropriate tools, such as authselect or authconfig, depending on the OS version.
Rationale
Locking out user accounts after a number of incorrect attempts prevents direct password guessing attacks. Ensuring that an administrator is involved in unlocking locked accounts draws appropriate attention to such situations.
Warnings
warning  If the system relies on authselect tool to manage PAM settings, the remediation will also use authselect tool. However, if any manual modification was made in PAM files, the authselect integrity check will fail and the remediation will be aborted in order to preserve intentional changes. In this case, an informative message will be shown in the remediation report. If the system supports the /etc/security/faillock.conf file, the pam_faillock parameters should be defined in faillock.conf file.

# Remediation is applicable only in certain platforms
if rpm --quiet -q pam; then

var_accounts_passwords_pam_faillock_unlock_time='0'


if [ -f /usr/bin/authselect ]; then
    if authselect check; then
    authselect enable-feature with-faillock
    authselect apply-changes
else
    echo "
authselect integrity check failed. Remediation aborted!
This remediation could not be applied because an authselect profile was not selected or the selected profile is not intact.
It is not recommended to manually edit the PAM files when authselect tool is available.
In cases where the default authselect profile does not cover a specific demand, a custom authselect profile is recommended."
    false
fi
else
    AUTH_FILES=("/etc/pam.d/system-auth" "/etc/pam.d/password-auth")
for pam_file in "${AUTH_FILES[@]}"
do
    if ! grep -qE '^\s*auth\s+required\s+pam_faillock\.so\s+(preauth silent|authfail).*$' "$pam_file" ; then
        sed -i --follow-symlinks '/^auth.*sufficient.*pam_unix.so.*/i auth        required      pam_faillock.so preauth silent' "$pam_file"
        sed -i --follow-symlinks '/^auth.*sufficient.*pam_unix.so.*/a auth        required      pam_faillock.so authfail' "$pam_file"
        sed -i --follow-symlinks '/^account.*required.*pam_unix.so.*/i account     required      pam_faillock.so' "$pam_file"
    fi
    sed -Ei 's/(auth.*)(\[default=die\])(.*pam_faillock.so)/\1required     \3/g' "$pam_file"
done
fi
FAILLOCK_CONF="/etc/security/faillock.conf"
if [ -f $FAILLOCK_CONF ]; then
    regex="^\s*unlock_time\s*="
    line="unlock_time = $var_accounts_passwords_pam_faillock_unlock_time"
    if ! grep -q $regex $FAILLOCK_CONF; then
        echo $line >> $FAILLOCK_CONF
    else
        sed -i --follow-symlinks 's/^\s*\(unlock_time\s*=\s*\)\([0-9]\+\)/\1'"$var_accounts_passwords_pam_faillock_unlock_time"'/g' $FAILLOCK_CONF
    fi
else
    AUTH_FILES=("/etc/pam.d/system-auth" "/etc/pam.d/password-auth")
    for pam_file in "${AUTH_FILES[@]}"
    do
        if ! grep -qE '^\s*auth.*pam_faillock.so (preauth|authfail).*unlock_time' "$pam_file"; then
            sed -i --follow-symlinks '/^auth.*required.*pam_faillock.so.*preauth.*silent.*/ s/$/ unlock_time='"$var_accounts_passwords_pam_faillock_unlock_time"'/' "$pam_file"
            sed -i --follow-symlinks '/^auth.*required.*pam_faillock.so.*authfail.*/ s/$/ unlock_time='"$var_accounts_passwords_pam_faillock_unlock_time"'/' "$pam_file"
        else
            sed -i --follow-symlinks 's/\(^auth.*required.*pam_faillock.so.*preauth.*silent.*\)\('"unlock_time"'=\)[0-9]\+\(.*\)/\1\2'"$var_accounts_passwords_pam_faillock_unlock_time"'\3/' "$pam_file"
            sed -i --follow-symlinks 's/\(^auth.*required.*pam_faillock.so.*authfail.*\)\('"unlock_time"'=\)[0-9]\+\(.*\)/\1\2'"$var_accounts_passwords_pam_faillock_unlock_time"'\3/' "$pam_file"
        fi
    done
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - CJIS-5.5.3
    - NIST-800-171-3.1.8
    - NIST-800-53-AC-7(b)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-8.1.7
    - accounts_passwords_pam_faillock_unlock_time
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Set Lockout Time for Failed Password Attempts - Check if system relies on
    authselect tool
  ansible.builtin.stat:
    path: /usr/bin/authselect
  register: result_authselect_present
  when: '"pam" in ansible_facts.packages'
  tags:
    - CJIS-5.5.3
    - NIST-800-171-3.1.8
    - NIST-800-53-AC-7(b)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-8.1.7
    - accounts_passwords_pam_faillock_unlock_time
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Set Lockout Time for Failed Password Attempts - Remediation where authselect
    tool is present
  block:

    - name: Set Lockout Time for Failed Password Attempts - Check integrity of authselect
        current profile
      ansible.builtin.command:
        cmd: authselect check
      register: result_authselect_check_cmd
      changed_when: false
      ignore_errors: true

    - name: Set Lockout Time for Failed Password Attempts - Informative message based
        on the authselect integrity check result
      ansible.builtin.assert:
        that:
          - result_authselect_check_cmd is success
        fail_msg:
          - authselect integrity check failed. Remediation aborted!
          - This remediation could not be applied because an authselect profile was
            not selected or the selected profile is not intact.
          - It is not recommended to manually edit the PAM files when authselect tool
            is available.
          - In cases where the default authselect profile does not cover a specific
            demand, a custom authselect profile is recommended.
        success_msg:
          - authselect integrity check passed

    - name: Set Lockout Time for Failed Password Attempts - Get authselect current
        features
      ansible.builtin.shell:
        cmd: authselect current | tail -n+3 | awk '{ print $2 }'
      register: result_authselect_features
      changed_when: false
      when:
        - result_authselect_check_cmd is success

    - name: Set Lockout Time for Failed Password Attempts - Ensure with-faillock feature
        is enabled using authselect tool
      ansible.builtin.command:
        cmd: authselect enable-feature with-faillock
      register: result_authselect_cmd
      when:
        - result_authselect_check_cmd is success
        - result_authselect_features.stdout is not search("with-faillock")
  when:
    - '"pam" in ansible_facts.packages'
    - result_authselect_present.stat.exists
  tags:
    - CJIS-5.5.3
    - NIST-800-171-3.1.8
    - NIST-800-53-AC-7(b)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-8.1.7
    - accounts_passwords_pam_faillock_unlock_time
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Set Lockout Time for Failed Password Attempts - Remediation where authselect
    tool is not present
  block:

    - name: Set Lockout Time for Failed Password Attempts - Check if pam_faillock.so
        is already enabled
      ansible.builtin.lineinfile:
        path: /etc/pam.d/system-auth
        regexp: .*auth.*pam_faillock.so (preauth|authfail)
        state: absent
      check_mode: true
      changed_when: false
      register: result_pam_faillock_is_enabled

    - name: Set Lockout Time for Failed Password Attempts - Enable pam_faillock.so
        preauth editing PAM files
      ansible.builtin.lineinfile:
        path: '{{ item }}'
        line: auth        required      pam_faillock.so preauth
        insertbefore: ^auth.*sufficient.*pam_unix.so.*
        state: present
      loop:
        - /etc/pam.d/system-auth
        - /etc/pam.d/password-auth
      when:
        - result_pam_faillock_is_enabled.found == 0

    - name: Set Lockout Time for Failed Password Attempts - Enable pam_faillock.so
        authfail editing PAM files
      ansible.builtin.lineinfile:
        path: '{{ item }}'
        line: auth        required      pam_faillock.so authfail
        insertafter: ^auth.*sufficient.*pam_unix.so.*
        state: present
      loop:
        - /etc/pam.d/system-auth
        - /etc/pam.d/password-auth
      when:
        - result_pam_faillock_is_enabled.found == 0

    - name: Set Lockout Time for Failed Password Attempts - Enable pam_faillock.so
        account section editing PAM files
      ansible.builtin.lineinfile:
        path: '{{ item }}'
        line: account     required      pam_faillock.so
        insertbefore: ^account.*required.*pam_unix.so.*
        state: present
      loop:
        - /etc/pam.d/system-auth
        - /etc/pam.d/password-auth
      when:
        - result_pam_faillock_is_enabled.found == 0
  when:
    - '"pam" in ansible_facts.packages'
    - not result_authselect_present.stat.exists
  tags:
    - CJIS-5.5.3
    - NIST-800-171-3.1.8
    - NIST-800-53-AC-7(b)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-8.1.7
    - accounts_passwords_pam_faillock_unlock_time
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
- name: XCCDF Value var_accounts_passwords_pam_faillock_unlock_time # promote to variable
  set_fact:
    var_accounts_passwords_pam_faillock_unlock_time: !!str 0
  tags:
    - always

- name: Set Lockout Time for Failed Password Attempts - Check the presence of /etc/security/faillock.conf
    file
  ansible.builtin.stat:
    path: /etc/security/faillock.conf
  register: result_faillock_conf_check
  when: '"pam" in ansible_facts.packages'
  tags:
    - CJIS-5.5.3
    - NIST-800-171-3.1.8
    - NIST-800-53-AC-7(b)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-8.1.7
    - accounts_passwords_pam_faillock_unlock_time
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Set Lockout Time for Failed Password Attempts - Ensure the pam_faillock.so
    unlock_time parameter in /etc/security/faillock.conf
  ansible.builtin.lineinfile:
    path: /etc/security/faillock.conf
    regexp: ^\s*unlock_time\s*=
    line: unlock_time = {{ var_accounts_passwords_pam_faillock_unlock_time }}
    state: present
  when:
    - '"pam" in ansible_facts.packages'
    - result_faillock_conf_check.stat.exists
  tags:
    - CJIS-5.5.3
    - NIST-800-171-3.1.8
    - NIST-800-53-AC-7(b)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-8.1.7
    - accounts_passwords_pam_faillock_unlock_time
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Set Lockout Time for Failed Password Attempts - Ensure the pam_faillock.so
    unlock_time parameter in PAM files
  block:

    - name: Set Lockout Time for Failed Password Attempts - Check if pam_faillock.so
        unlock_time parameter is already enabled in pam files
      ansible.builtin.lineinfile:
        path: /etc/pam.d/system-auth
        regexp: .*auth.*pam_faillock.so (preauth|authfail).*unlock_time
        state: absent
      check_mode: true
      changed_when: false
      register: result_pam_faillock_unlock_time_parameter_is_present

    - name: Set Lockout Time for Failed Password Attempts - Ensure the inclusion of
        pam_faillock.so preauth unlock_time parameter in auth section
      ansible.builtin.lineinfile:
        path: '{{ item }}'
        backrefs: true
        regexp: (^\s*auth\s+)([\w\[].*\b)(\s+pam_faillock.so preauth.*)
        line: \1required\3 unlock_time={{ var_accounts_passwords_pam_faillock_unlock_time
          }}
        state: present
      loop:
        - /etc/pam.d/system-auth
        - /etc/pam.d/password-auth
      when:
        - result_pam_faillock_unlock_time_parameter_is_present.found == 0

    - name: Set Lockout Time for Failed Password Attempts - Ensure the inclusion of
        pam_faillock.so authfail unlock_time parameter in auth section
      ansible.builtin.lineinfile:
        path: '{{ item }}'
        backrefs: true
        regexp: (^\s*auth\s+)([\w\[].*\b)(\s+pam_faillock.so authfail.*)
        line: \1required\3 unlock_time={{ var_accounts_passwords_pam_faillock_unlock_time
          }}
        state: present
      loop:
        - /etc/pam.d/system-auth
        - /etc/pam.d/password-auth
      when:
        - result_pam_faillock_unlock_time_parameter_is_present.found == 0

    - name: Set Lockout Time for Failed Password Attempts - Ensure the desired value
        for pam_faillock.so preauth unlock_time parameter in auth section
      ansible.builtin.lineinfile:
        path: '{{ item }}'
        backrefs: true
        regexp: (^\s*auth\s+)([\w\[].*\b)(\s+pam_faillock.so preauth.*)(unlock_time)=[0-9]+(.*)
        line: \1required\3\4={{ var_accounts_passwords_pam_faillock_unlock_time }}\5
        state: present
      loop:
        - /etc/pam.d/system-auth
        - /etc/pam.d/password-auth
      when:
        - result_pam_faillock_unlock_time_parameter_is_present.found > 0

    - name: Set Lockout Time for Failed Password Attempts - Ensure the desired value
        for pam_faillock.so authfail unlock_time parameter in auth section
      ansible.builtin.lineinfile:
        path: '{{ item }}'
        backrefs: true
        regexp: (^\s*auth\s+)([\w\[].*\b)(\s+pam_faillock.so authfail.*)(unlock_time)=[0-9]+(.*)
        line: \1required\3\4={{ var_accounts_passwords_pam_faillock_unlock_time }}\5
        state: present
      loop:
        - /etc/pam.d/system-auth
        - /etc/pam.d/password-auth
      when:
        - result_pam_faillock_unlock_time_parameter_is_present.found > 0
  when:
    - '"pam" in ansible_facts.packages'
    - not result_faillock_conf_check.stat.exists
  tags:
    - CJIS-5.5.3
    - NIST-800-171-3.1.8
    - NIST-800-53-AC-7(b)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-8.1.7
    - accounts_passwords_pam_faillock_unlock_time
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

No more than one pam_unix.so is expected in auth section of system-auth  oval:ssg-test_accounts_passwords_pam_faillock_unlock_time_system_pam_unix_auth:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_unlock_time_system_pam_unix_auth:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*auth\N+pam_unix\.so^/etc/pam.d/system-auth$1

No more than one pam_unix.so is expected in auth section of password-auth  oval:ssg-test_accounts_passwords_pam_faillock_unlock_time_password_pam_unix_auth:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_unlock_time_password_pam_unix_auth:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*auth\N+pam_unix\.so^/etc/pam.d/password-auth$1

One and only one occurrence is expected in auth section of system-auth  oval:ssg-test_accounts_passwords_pam_faillock_unlock_time_system_pam_faillock_auth:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_unlock_time_system_pam_faillock_auth:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*auth[\s]+(required|\[(?=.*?\bsuccess=ok\b)(?=.*?\bnew_authtok_reqd=ok\b)(?=.*?\bignore=ignore\b)(?=.*?\bdefault=bad\b).*\])[\s]+pam_faillock\.so[\s\w\d=]+preauth[\s\S]*^[\s]*auth[\s]+(sufficient|\[(?=.*\bsuccess=done\b)(?=.*?\bnew_authtok_reqd=done\b)(?=.*?\bdefault=ignore\b).*\])[\s]+pam_unix\.so[\s\S]*^[\s]*auth[\s]+(required|\[(?=.*?\bsuccess=ok\b)(?=.*?\bnew_authtok_reqd=ok\b)(?=.*?\bignore=ignore\b)(?=.*?\bdefault=bad\b).*\])[\s]+pam_faillock\.so[\s\w\d=]+authfail^/etc/pam.d/system-auth$1

One and only one occurrence is expected in auth section of system-auth  oval:ssg-test_accounts_passwords_pam_faillock_unlock_time_system_pam_faillock_account:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_unlock_time_system_pam_faillock_account:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*account[\s]+(required|\[(?=.*?\bsuccess=ok\b)(?=.*?\bnew_authtok_reqd=ok\b)(?=.*?\bignore=ignore\b)(?=.*?\bdefault=bad\b).*\])[\s]+pam_faillock\.so[\s\S]*^[\s]*account[\s]+(required|\[(?=.*?\bsuccess=ok\b)(?=.*?\bnew_authtok_reqd=ok\b)(?=.*?\bignore=ignore\b)(?=.*?\bdefault=bad\b).*\])[\s]+pam_unix\.so^/etc/pam.d/system-auth$1

One and only one occurrence is expected in auth section of password-auth  oval:ssg-test_accounts_passwords_pam_faillock_unlock_time_password_pam_faillock_auth:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_unlock_time_password_pam_faillock_auth:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*auth[\s]+(required|\[(?=.*?\bsuccess=ok\b)(?=.*?\bnew_authtok_reqd=ok\b)(?=.*?\bignore=ignore\b)(?=.*?\bdefault=bad\b).*\])[\s]+pam_faillock\.so[\s\w\d=]+preauth[\s\S]*^[\s]*auth[\s]+(sufficient|\[(?=.*\bsuccess=done\b)(?=.*?\bnew_authtok_reqd=done\b)(?=.*?\bdefault=ignore\b).*\])[\s]+pam_unix\.so[\s\S]*^[\s]*auth[\s]+(required|\[(?=.*?\bsuccess=ok\b)(?=.*?\bnew_authtok_reqd=ok\b)(?=.*?\bignore=ignore\b)(?=.*?\bdefault=bad\b).*\])[\s]+pam_faillock\.so[\s\w\d=]+authfail^/etc/pam.d/password-auth$1

One and only one occurrence is expected in auth section of password-auth  oval:ssg-test_accounts_passwords_pam_faillock_unlock_time_password_pam_faillock_account:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_unlock_time_password_pam_faillock_account:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*account[\s]+(required|\[(?=.*?\bsuccess=ok\b)(?=.*?\bnew_authtok_reqd=ok\b)(?=.*?\bignore=ignore\b)(?=.*?\bdefault=bad\b).*\])[\s]+pam_faillock\.so[\s\S]*^[\s]*account[\s]+(required|\[(?=.*?\bsuccess=ok\b)(?=.*?\bnew_authtok_reqd=ok\b)(?=.*?\bignore=ignore\b)(?=.*?\bdefault=bad\b).*\])[\s]+pam_unix\.so^/etc/pam.d/password-auth$1

Check the expected unlock_time value in system-auth  oval:ssg-test_accounts_passwords_pam_faillock_unlock_time_parameter_pamd_system:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_unlock_time_parameter_pamd_system:obj:1 of type textfilecontent54_object
FilepathPatternInstance
0
^[\s]*auth[\s]+.+[\s]+pam_faillock.so[\s]+[^\n]*unlock_time=([0-9]+)
^/etc/pam.d/system-auth$1

Check the expected unlock_time value in password-auth  oval:ssg-test_accounts_passwords_pam_faillock_unlock_time_parameter_pamd_password:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_unlock_time_parameter_pamd_password:obj:1 of type textfilecontent54_object
FilepathPatternInstance
0
^[\s]*auth[\s]+.+[\s]+pam_faillock.so[\s]+[^\n]*unlock_time=([0-9]+)
^/etc/pam.d/password-auth$1

Check the absence of unlock_time parameter in /etc/security/faillock.conf  oval:ssg-test_accounts_passwords_pam_faillock_unlock_time_parameter_no_faillock_conf:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_unlock_time_parameter_faillock_conf:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*unlock_time[\s]*=[\s]*([0-9]+)^/etc/security/faillock.conf$1

Check the absence of unlock_time parameter in system-auth  oval:ssg-test_accounts_passwords_pam_faillock_unlock_time_parameter_no_pamd_system:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_unlock_time_parameter_pamd_system:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*auth[\s]+.+[\s]+pam_faillock.so[\s]+[^\n]*unlock_time=([0-9]+)^/etc/pam.d/system-auth$1

Check the absence of unlock_time parameter in password-auth  oval:ssg-test_accounts_passwords_pam_faillock_unlock_time_parameter_no_pamd_password:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_unlock_time_parameter_pamd_password:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*auth[\s]+.+[\s]+pam_faillock.so[\s]+[^\n]*unlock_time=([0-9]+)^/etc/pam.d/password-auth$1

Check the expected unlock_time value in in /etc/security/faillock.conf  oval:ssg-test_accounts_passwords_pam_faillock_unlock_time_parameter_faillock_conf:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_accounts_passwords_pam_faillock_unlock_time_parameter_faillock_conf:obj:1 of type textfilecontent54_object
FilepathPatternInstance
0
^[\s]*unlock_time[\s]*=[\s]*([0-9]+)
^/etc/security/faillock.conf$1
Ensure PAM Enforces Password Requirements - Minimum Digit Charactersxccdf_org.ssgproject.content_rule_accounts_password_pam_dcredit medium

Ensure PAM Enforces Password Requirements - Minimum Digit Characters

Rule IDxccdf_org.ssgproject.content_rule_accounts_password_pam_dcredit
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-accounts_password_pam_dcredit:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  BP28(R18), 1, 12, 15, 16, 5, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.10, CCI-000194, 4.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.2, 4.3.3.7.4, SR 1.1, SR 1.10, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1, 0421, 0422, 0431, 0974, 1173, 1401, 1504, 1505, 1546, 1557, 1558, 1559, 1560, 1561, A.18.1.4, A.7.1.1, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.2, A.9.4.3, IA-5(c), IA-5(1)(a), CM-6(a), IA-5(4), PR.AC-1, PR.AC-6, PR.AC-7, FMT_MOF_EXT.1, Req-8.2.3, SRG-OS-000071-GPOS-00039, SRG-OS-000071-VMM-000380

Description
The pam_pwquality module's dcredit parameter controls requirements for usage of digits in a password. When set to a negative number, any password will be required to contain that many digits. When set to a positive number, pam_pwquality will grant +1 additional length credit for each digit. Modify the dcredit setting in /etc/security/pwquality.conf to require the use of a digit in passwords.
Rationale
Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks.

Password complexity is one factor of several that determines how long it takes to crack a password. The more complex the password, the greater the number of possible combinations that need to be tested before the password is compromised. Requiring digits makes password guessing attacks more difficult by ensuring a larger search space.

Complexity:low
Disruption:low
Strategy:restrict
# Remediation is applicable only in certain platforms
if rpm --quiet -q pam; then

var_password_pam_dcredit='-1'


# Test if the config_file is a symbolic link. If so, use --follow-symlinks with sed.
# Otherwise, regular sed command will do.
sed_command=('sed' '-i')
if test -L "/etc/security/pwquality.conf"; then
    sed_command+=('--follow-symlinks')
fi

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^dcredit")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "$var_password_pam_dcredit"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^dcredit\\>" "/etc/security/pwquality.conf"; then
    "${sed_command[@]}" "s/^dcredit\\>.*/$formatted_output/gi" "/etc/security/pwquality.conf"
else
    # \n is precaution for case where file ends without trailing newline
    
    printf '%s\n' "$formatted_output" >> "/etc/security/pwquality.conf"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-CM-6(a)
    - NIST-800-53-IA-5(1)(a)
    - NIST-800-53-IA-5(4)
    - NIST-800-53-IA-5(c)
    - PCI-DSS-Req-8.2.3
    - accounts_password_pam_dcredit
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
- name: XCCDF Value var_password_pam_dcredit # promote to variable
  set_fact:
    var_password_pam_dcredit: !!str -1
  tags:
    - always

- name: Ensure PAM variable dcredit is set accordingly
  lineinfile:
    create: true
    dest: /etc/security/pwquality.conf
    regexp: ^#?\s*dcredit
    line: dcredit = {{ var_password_pam_dcredit }}
  when: '"pam" in ansible_facts.packages'
  tags:
    - NIST-800-53-CM-6(a)
    - NIST-800-53-IA-5(1)(a)
    - NIST-800-53-IA-5(4)
    - NIST-800-53-IA-5(c)
    - PCI-DSS-Req-8.2.3
    - accounts_password_pam_dcredit
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

check the configuration of /etc/pam.d/system-auth  oval:ssg-test_password_pam_pwquality:tst:1  true

Following items have been found on the system:
PathContent
/etc/pam.d/system-auth password requisite pam_pwquality.so try_first_pass local_users_only

check the configuration of /etc/security/pwquality.conf  oval:ssg-test_password_pam_pwquality_dcredit:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_password_pam_pwquality_dcredit:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/security/pwquality.conf^dcredit[\s]*=[\s]*(-?\d+)(?:[\s]|$)1
Ensure PAM Enforces Password Requirements - Minimum Lowercase Charactersxccdf_org.ssgproject.content_rule_accounts_password_pam_lcredit medium

Ensure PAM Enforces Password Requirements - Minimum Lowercase Characters

Rule IDxccdf_org.ssgproject.content_rule_accounts_password_pam_lcredit
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-accounts_password_pam_lcredit:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  BP28(R18), 1, 12, 15, 16, 5, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.10, CCI-000193, 4.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.2, 4.3.3.7.4, SR 1.1, SR 1.10, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1, 0421, 0422, 0431, 0974, 1173, 1401, 1504, 1505, 1546, 1557, 1558, 1559, 1560, 1561, A.18.1.4, A.7.1.1, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.2, A.9.4.3, IA-5(c), IA-5(1)(a), CM-6(a), IA-5(4), PR.AC-1, PR.AC-6, PR.AC-7, FMT_MOF_EXT.1, Req-8.2.3, SRG-OS-000070-GPOS-00038, SRG-OS-000070-VMM-000370

Description
The pam_pwquality module's lcredit parameter controls requirements for usage of lowercase letters in a password. When set to a negative number, any password will be required to contain that many lowercase characters. When set to a positive number, pam_pwquality will grant +1 additional length credit for each lowercase character. Modify the lcredit setting in /etc/security/pwquality.conf to require the use of a lowercase character in passwords.
Rationale
Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks.

Password complexity is one factor of several that determines how long it takes to crack a password. The more complex the password, the greater the number of possble combinations that need to be tested before the password is compromised. Requiring a minimum number of lowercase characters makes password guessing attacks more difficult by ensuring a larger search space.

Complexity:low
Disruption:low
Strategy:restrict
# Remediation is applicable only in certain platforms
if rpm --quiet -q pam; then

var_password_pam_lcredit='-1'


# Test if the config_file is a symbolic link. If so, use --follow-symlinks with sed.
# Otherwise, regular sed command will do.
sed_command=('sed' '-i')
if test -L "/etc/security/pwquality.conf"; then
    sed_command+=('--follow-symlinks')
fi

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^lcredit")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "$var_password_pam_lcredit"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^lcredit\\>" "/etc/security/pwquality.conf"; then
    "${sed_command[@]}" "s/^lcredit\\>.*/$formatted_output/gi" "/etc/security/pwquality.conf"
else
    # \n is precaution for case where file ends without trailing newline
    
    printf '%s\n' "$formatted_output" >> "/etc/security/pwquality.conf"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-CM-6(a)
    - NIST-800-53-IA-5(1)(a)
    - NIST-800-53-IA-5(4)
    - NIST-800-53-IA-5(c)
    - PCI-DSS-Req-8.2.3
    - accounts_password_pam_lcredit
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
- name: XCCDF Value var_password_pam_lcredit # promote to variable
  set_fact:
    var_password_pam_lcredit: !!str -1
  tags:
    - always

- name: Ensure PAM variable lcredit is set accordingly
  lineinfile:
    create: true
    dest: /etc/security/pwquality.conf
    regexp: ^#?\s*lcredit
    line: lcredit = {{ var_password_pam_lcredit }}
  when: '"pam" in ansible_facts.packages'
  tags:
    - NIST-800-53-CM-6(a)
    - NIST-800-53-IA-5(1)(a)
    - NIST-800-53-IA-5(4)
    - NIST-800-53-IA-5(c)
    - PCI-DSS-Req-8.2.3
    - accounts_password_pam_lcredit
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

check the configuration of /etc/pam.d/system-auth  oval:ssg-test_password_pam_pwquality:tst:1  true

Following items have been found on the system:
PathContent
/etc/pam.d/system-auth password requisite pam_pwquality.so try_first_pass local_users_only

check the configuration of /etc/security/pwquality.conf  oval:ssg-test_password_pam_pwquality_lcredit:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_password_pam_pwquality_lcredit:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/security/pwquality.conf^lcredit[\s]*=[\s]*(-?\d+)(?:[\s]|$)1
Ensure PAM Enforces Password Requirements - Minimum Lengthxccdf_org.ssgproject.content_rule_accounts_password_pam_minlen medium

Ensure PAM Enforces Password Requirements - Minimum Length

Rule IDxccdf_org.ssgproject.content_rule_accounts_password_pam_minlen
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-accounts_password_pam_minlen:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  BP28(R18), 1, 12, 15, 16, 5, 5.6.2.1.1, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.10, CCI-000205, 4.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.2, 4.3.3.7.4, SR 1.1, SR 1.10, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1, 0421, 0422, 0431, 0974, 1173, 1401, 1504, 1505, 1546, 1557, 1558, 1559, 1560, 1561, A.18.1.4, A.7.1.1, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.2, A.9.4.3, IA-5(c), IA-5(1)(a), CM-6(a), IA-5(4), PR.AC-1, PR.AC-6, PR.AC-7, FMT_MOF_EXT.1, Req-8.2.3, SRG-OS-000078-GPOS-00046, SRG-OS-000072-VMM-000390, SRG-OS-000078-VMM-000450

Description
The pam_pwquality module's minlen parameter controls requirements for minimum characters required in a password. Add minlen=12 after pam_pwquality to set minimum password length requirements.
Rationale
The shorter the password, the lower the number of possible combinations that need to be tested before the password is compromised.
Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks. Password length is one factor of several that helps to determine strength and how long it takes to crack a password. Use of more characters in a password helps to exponentially increase the time and/or resources required to compromose the password.

Complexity:low
Disruption:low
Strategy:restrict
# Remediation is applicable only in certain platforms
if rpm --quiet -q pam; then

var_password_pam_minlen='12'


# Test if the config_file is a symbolic link. If so, use --follow-symlinks with sed.
# Otherwise, regular sed command will do.
sed_command=('sed' '-i')
if test -L "/etc/security/pwquality.conf"; then
    sed_command+=('--follow-symlinks')
fi

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^minlen")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "$var_password_pam_minlen"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^minlen\\>" "/etc/security/pwquality.conf"; then
    "${sed_command[@]}" "s/^minlen\\>.*/$formatted_output/gi" "/etc/security/pwquality.conf"
else
    # \n is precaution for case where file ends without trailing newline
    
    printf '%s\n' "$formatted_output" >> "/etc/security/pwquality.conf"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - CJIS-5.6.2.1.1
    - NIST-800-53-CM-6(a)
    - NIST-800-53-IA-5(1)(a)
    - NIST-800-53-IA-5(4)
    - NIST-800-53-IA-5(c)
    - PCI-DSS-Req-8.2.3
    - accounts_password_pam_minlen
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
- name: XCCDF Value var_password_pam_minlen # promote to variable
  set_fact:
    var_password_pam_minlen: !!str 12
  tags:
    - always

- name: Ensure PAM variable minlen is set accordingly
  lineinfile:
    create: true
    dest: /etc/security/pwquality.conf
    regexp: ^#?\s*minlen
    line: minlen = {{ var_password_pam_minlen }}
  when: '"pam" in ansible_facts.packages'
  tags:
    - CJIS-5.6.2.1.1
    - NIST-800-53-CM-6(a)
    - NIST-800-53-IA-5(1)(a)
    - NIST-800-53-IA-5(4)
    - NIST-800-53-IA-5(c)
    - PCI-DSS-Req-8.2.3
    - accounts_password_pam_minlen
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

check the configuration of /etc/pam.d/system-auth  oval:ssg-test_password_pam_pwquality:tst:1  true

Following items have been found on the system:
PathContent
/etc/pam.d/system-auth password requisite pam_pwquality.so try_first_pass local_users_only

check the configuration of /etc/security/pwquality.conf  oval:ssg-test_password_pam_pwquality_minlen:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_password_pam_pwquality_minlen:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/security/pwquality.conf^minlen[\s]*=[\s]*(\d+)(?:[\s]|$)1
Ensure PAM Enforces Password Requirements - Minimum Special Charactersxccdf_org.ssgproject.content_rule_accounts_password_pam_ocredit medium

Ensure PAM Enforces Password Requirements - Minimum Special Characters

Rule IDxccdf_org.ssgproject.content_rule_accounts_password_pam_ocredit
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-accounts_password_pam_ocredit:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  BP28(R18), 1, 12, 15, 16, 5, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.10, CCI-001619, 4.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.2, 4.3.3.7.4, SR 1.1, SR 1.10, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1, 0421, 0422, 0431, 0974, 1173, 1401, 1504, 1505, 1546, 1557, 1558, 1559, 1560, 1561, A.18.1.4, A.7.1.1, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.2, A.9.4.3, IA-5(c), IA-5(1)(a), CM-6(a), IA-5(4), PR.AC-1, PR.AC-6, PR.AC-7, FMT_MOF_EXT.1, SRG-OS-000266-GPOS-00101, SRG-OS-000266-VMM-000940

Description
The pam_pwquality module's ocredit= parameter controls requirements for usage of special (or "other") characters in a password. When set to a negative number, any password will be required to contain that many special characters. When set to a positive number, pam_pwquality will grant +1 additional length credit for each special character. Modify the ocredit setting in /etc/security/pwquality.conf to equal -1 to require use of a special character in passwords.
Rationale
Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks.

Password complexity is one factor of several that determines how long it takes to crack a password. The more complex the password, the greater the number of possble combinations that need to be tested before the password is compromised. Requiring a minimum number of special characters makes password guessing attacks more difficult by ensuring a larger search space.

Complexity:low
Disruption:low
Strategy:restrict
# Remediation is applicable only in certain platforms
if rpm --quiet -q pam; then

var_password_pam_ocredit='-1'


# Test if the config_file is a symbolic link. If so, use --follow-symlinks with sed.
# Otherwise, regular sed command will do.
sed_command=('sed' '-i')
if test -L "/etc/security/pwquality.conf"; then
    sed_command+=('--follow-symlinks')
fi

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^ocredit")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "$var_password_pam_ocredit"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^ocredit\\>" "/etc/security/pwquality.conf"; then
    "${sed_command[@]}" "s/^ocredit\\>.*/$formatted_output/gi" "/etc/security/pwquality.conf"
else
    # \n is precaution for case where file ends without trailing newline
    
    printf '%s\n' "$formatted_output" >> "/etc/security/pwquality.conf"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-CM-6(a)
    - NIST-800-53-IA-5(1)(a)
    - NIST-800-53-IA-5(4)
    - NIST-800-53-IA-5(c)
    - accounts_password_pam_ocredit
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
- name: XCCDF Value var_password_pam_ocredit # promote to variable
  set_fact:
    var_password_pam_ocredit: !!str -1
  tags:
    - always

- name: Ensure PAM variable ocredit is set accordingly
  lineinfile:
    create: true
    dest: /etc/security/pwquality.conf
    regexp: ^#?\s*ocredit
    line: ocredit = {{ var_password_pam_ocredit }}
  when: '"pam" in ansible_facts.packages'
  tags:
    - NIST-800-53-CM-6(a)
    - NIST-800-53-IA-5(1)(a)
    - NIST-800-53-IA-5(4)
    - NIST-800-53-IA-5(c)
    - accounts_password_pam_ocredit
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

check the configuration of /etc/pam.d/system-auth  oval:ssg-test_password_pam_pwquality:tst:1  true

Following items have been found on the system:
PathContent
/etc/pam.d/system-auth password requisite pam_pwquality.so try_first_pass local_users_only

check the configuration of /etc/security/pwquality.conf  oval:ssg-test_password_pam_pwquality_ocredit:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_password_pam_pwquality_ocredit:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/security/pwquality.conf^ocredit[\s]*=[\s]*(-?\d+)(?:[\s]|$)1
Ensure PAM Enforces Password Requirements - Authentication Retry Prompts Permitted Per-Sessionxccdf_org.ssgproject.content_rule_accounts_password_pam_retry medium

Ensure PAM Enforces Password Requirements - Authentication Retry Prompts Permitted Per-Session

Rule IDxccdf_org.ssgproject.content_rule_accounts_password_pam_retry
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-accounts_password_pam_retry:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 15, 16, 3, 5, 9, 5.5.3, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.10, CCI-000192, CCI-000366, 4.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.2, 4.3.3.7.4, 4.3.4.3.2, 4.3.4.3.3, SR 1.1, SR 1.10, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 7.6, A.12.1.2, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4, A.18.1.4, A.7.1.1, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.2, A.9.4.3, CM-6(a), AC-7(a), IA-5(4), PR.AC-1, PR.AC-6, PR.AC-7, PR.IP-1, FMT_MOF_EXT.1, SRG-OS-000480-GPOS-00225, SRG-OS-000069-GPOS-00037

Description
To configure the number of retry prompts that are permitted per-session: Edit the pam_pwquality.so statement in /etc/pam.d/system-auth to show retry=3, or a lower value if site policy is more restrictive. The DoD requirement is a maximum of 3 prompts per session.
Rationale
Setting the password retry prompts that are permitted on a per-session basis to a low value requires some software, such as SSH, to re-connect. This can slow down and draw additional attention to some types of password-guessing attacks. Note that this is different from account lockout, which is provided by the pam_faillock module.

# Remediation is applicable only in certain platforms
if rpm --quiet -q pam; then

var_password_pam_retry='3'



	if grep -q "retry=" /etc/pam.d/system-auth ; then
		sed -i --follow-symlinks "s/\(retry *= *\).*/\1$var_password_pam_retry/" /etc/pam.d/system-auth
	else
		sed -i --follow-symlinks "/pam_pwquality.so/ s/$/ retry=$var_password_pam_retry/" /etc/pam.d/system-auth
	fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:medium
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - CJIS-5.5.3
    - NIST-800-53-AC-7(a)
    - NIST-800-53-CM-6(a)
    - NIST-800-53-IA-5(4)
    - accounts_password_pam_retry
    - configure_strategy
    - low_complexity
    - medium_disruption
    - medium_severity
    - no_reboot_needed
- name: XCCDF Value var_password_pam_retry # promote to variable
  set_fact:
    var_password_pam_retry: !!str 3
  tags:
    - always

- name: Set Password Retry Prompts Permitted Per-Session - system-auth (change)
  replace:
    dest: /etc/pam.d/system-auth
    regexp: (^.*\spam_pwquality.so\s.*retry\s*=\s*)(\S+)(.*$)
    replace: \g<1>{{ var_password_pam_retry }}\g<3>
  when: '"pam" in ansible_facts.packages'
  tags:
    - CJIS-5.5.3
    - NIST-800-53-AC-7(a)
    - NIST-800-53-CM-6(a)
    - NIST-800-53-IA-5(4)
    - accounts_password_pam_retry
    - configure_strategy
    - low_complexity
    - medium_disruption
    - medium_severity
    - no_reboot_needed

- name: Set Password Retry Prompts Permitted Per-Session - system-auth (add)
  replace:
    dest: /etc/pam.d/system-auth
    regexp: ^.*\spam_pwquality.so\s(?!.*retry\s*=\s*).*$
    replace: \g<0> retry={{ var_password_pam_retry }}
  when: '"pam" in ansible_facts.packages'
  tags:
    - CJIS-5.5.3
    - NIST-800-53-AC-7(a)
    - NIST-800-53-CM-6(a)
    - NIST-800-53-IA-5(4)
    - accounts_password_pam_retry
    - configure_strategy
    - low_complexity
    - medium_disruption
    - medium_severity
    - no_reboot_needed
OVAL test results details

check the configuration of /etc/pam.d/system-auth  oval:ssg-test_password_pam_pwquality_retry_system_auth:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_password_pam_pwquality_retry_system_auth:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/pam.d/system-auth^\s*password\s+(?:(?:required)|(?:requisite))\s+pam_pwquality\.so.*retry=([0-9]*).*$1

check the configuration of /etc/pam.d/system-auth  oval:ssg-test_password_pam_pwquality:tst:1  true

Following items have been found on the system:
PathContent
/etc/pam.d/system-auth password requisite pam_pwquality.so try_first_pass local_users_only

check the configuration of /etc/security/pwquality.conf  oval:ssg-test_password_pam_pwquality_retry_pwquality_conf:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_password_pam_pwquality_retry_pwquality_conf:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/security/pwquality.conf^retry[\s]*=[\s]*(\d+)(?:[\s]|$)1
Ensure PAM Enforces Password Requirements - Minimum Uppercase Charactersxccdf_org.ssgproject.content_rule_accounts_password_pam_ucredit medium

Ensure PAM Enforces Password Requirements - Minimum Uppercase Characters

Rule IDxccdf_org.ssgproject.content_rule_accounts_password_pam_ucredit
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-accounts_password_pam_ucredit:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  BP28(R18), 1, 12, 15, 16, 5, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.10, CCI-000192, 4.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.2, 4.3.3.7.4, SR 1.1, SR 1.10, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1, 0421, 0422, 0431, 0974, 1173, 1401, 1504, 1505, 1546, 1557, 1558, 1559, 1560, 1561, A.18.1.4, A.7.1.1, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.2, A.9.4.3, IA-5(c), IA-5(1)(a), CM-6(a), IA-5(4), PR.AC-1, PR.AC-6, PR.AC-7, FMT_MOF_EXT.1, Req-8.2.3, SRG-OS-000069-GPOS-00037, SRG-OS-000069-VMM-000360

Description
The pam_pwquality module's ucredit= parameter controls requirements for usage of uppercase letters in a password. When set to a negative number, any password will be required to contain that many uppercase characters. When set to a positive number, pam_pwquality will grant +1 additional length credit for each uppercase character. Modify the ucredit setting in /etc/security/pwquality.conf to require the use of an uppercase character in passwords.
Rationale
Use of a complex password helps to increase the time and resources reuiqred to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks.

Password complexity is one factor of several that determines how long it takes to crack a password. The more complex the password, the greater the number of possible combinations that need to be tested before the password is compromised.

Complexity:low
Disruption:low
Strategy:restrict
# Remediation is applicable only in certain platforms
if rpm --quiet -q pam; then

var_password_pam_ucredit='-1'


# Test if the config_file is a symbolic link. If so, use --follow-symlinks with sed.
# Otherwise, regular sed command will do.
sed_command=('sed' '-i')
if test -L "/etc/security/pwquality.conf"; then
    sed_command+=('--follow-symlinks')
fi

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^ucredit")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "$var_password_pam_ucredit"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^ucredit\\>" "/etc/security/pwquality.conf"; then
    "${sed_command[@]}" "s/^ucredit\\>.*/$formatted_output/gi" "/etc/security/pwquality.conf"
else
    # \n is precaution for case where file ends without trailing newline
    
    printf '%s\n' "$formatted_output" >> "/etc/security/pwquality.conf"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-CM-6(a)
    - NIST-800-53-IA-5(1)(a)
    - NIST-800-53-IA-5(4)
    - NIST-800-53-IA-5(c)
    - PCI-DSS-Req-8.2.3
    - accounts_password_pam_ucredit
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
- name: XCCDF Value var_password_pam_ucredit # promote to variable
  set_fact:
    var_password_pam_ucredit: !!str -1
  tags:
    - always

- name: Ensure PAM variable ucredit is set accordingly
  lineinfile:
    create: true
    dest: /etc/security/pwquality.conf
    regexp: ^#?\s*ucredit
    line: ucredit = {{ var_password_pam_ucredit }}
  when: '"pam" in ansible_facts.packages'
  tags:
    - NIST-800-53-CM-6(a)
    - NIST-800-53-IA-5(1)(a)
    - NIST-800-53-IA-5(4)
    - NIST-800-53-IA-5(c)
    - PCI-DSS-Req-8.2.3
    - accounts_password_pam_ucredit
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

check the configuration of /etc/pam.d/system-auth  oval:ssg-test_password_pam_pwquality:tst:1  true

Following items have been found on the system:
PathContent
/etc/pam.d/system-auth password requisite pam_pwquality.so try_first_pass local_users_only

check the configuration of /etc/security/pwquality.conf  oval:ssg-test_password_pam_pwquality_ucredit:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_password_pam_pwquality_ucredit:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/security/pwquality.conf^ucredit[\s]*=[\s]*(-?\d+)(?:[\s]|$)1
Install the screen Packagexccdf_org.ssgproject.content_rule_package_screen_installed medium

Install the screen Package

Rule IDxccdf_org.ssgproject.content_rule_package_screen_installed
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-package_screen_installed:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 12, 15, 16, DSS05.04, DSS05.10, DSS06.10, 3.1.10, CCI-000057, CCI-000058, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, SR 1.1, SR 1.10, SR 1.2, SR 1.5, SR 1.7, SR 1.8, SR 1.9, A.18.1.4, A.9.2.1, A.9.2.4, A.9.3.1, A.9.4.2, A.9.4.3, CM-6(a), PR.AC-7, FMT_MOF_EXT.1, SRG-OS-000029-GPOS-00010, SRG-OS-000030-VMM-000110

Description
To enable console screen locking, install the screen package. The screen package can be installed with the following command:
$ sudo dnf install screen
Instruct users to begin new terminal sessions with the following command:
$ screen
The console can now be locked with the following key combination:
ctrl+a x
Rationale
A session time-out lock is a temporary action taken when a user stops work and moves away from the immediate physical vicinity of the information system but does not logout because of the temporary nature of the absence. Rather than relying on the user to manually lock their operation system session prior to vacating the vicinity, operating systems need to be able to identify when a user's session has idled and take action to initiate the session lock.

The screen package allows for a session lock to be implemented and configured.

Complexity:low
Disruption:low
Strategy:enable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

if ! rpm -q --quiet "screen" ; then
    dnf install -y "screen"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:enable
- name: Ensure screen is installed
  package:
    name: screen
    state: present
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-171-3.1.10
    - NIST-800-53-CM-6(a)
    - enable_strategy
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - package_screen_installed

Complexity:low
Disruption:low
Strategy:enable
include install_screen

class install_screen {
  package { 'screen':
    ensure => 'installed',
  }
}

Complexity:low
Disruption:low
Strategy:enable

package --add=screen


[[packages]]
name = "screen"
version = "*"
OVAL test results details

package screen is installed  oval:ssg-test_package_screen_installed:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_test_package_screen_installed:obj:1 of type rpminfo_object
Name
screen
Disable debug-shell SystemD Servicexccdf_org.ssgproject.content_rule_service_debug-shell_disabled medium

Disable debug-shell SystemD Service

Rule IDxccdf_org.ssgproject.content_rule_service_debug-shell_disabled
Result
pass
Multi-check ruleno
OVAL Definition IDoval:ssg-service_debug-shell_disabled:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  3.4.5, CCI-000366, 164.308(a)(1)(ii)(B), 164.308(a)(7)(i), 164.308(a)(7)(ii)(A), 164.310(a)(1), 164.310(a)(2)(i), 164.310(a)(2)(ii), 164.310(a)(2)(iii), 164.310(b), 164.310(c), 164.310(d)(1), 164.310(d)(2)(iii), CM-6, FIA_UAU.1, SRG-OS-000324-GPOS-00125, SRG-OS-000480-GPOS-00227

Description
SystemD's debug-shell service is intended to diagnose SystemD related boot issues with various systemctl commands. Once enabled and following a system reboot, the root shell will be available on tty9 which is access by pressing CTRL-ALT-F9. The debug-shell service should only be used for SystemD related issues and should otherwise be disabled.

By default, the debug-shell SystemD service is already disabled. The debug-shell service can be disabled with the following command:
$ sudo systemctl mask --now debug-shell.service
Rationale
This prevents attackers with physical access from trivially bypassing security on the machine through valid troubleshooting configurations and gaining root access when the system is rebooted.
OVAL test results details

package systemd is removed  oval:ssg-test_service_debug-shell_package_systemd_removed:tst:1  false

Following items have been found on the system:
NameArchEpochReleaseVersionEvrSignature keyidExtended name
systemdx86_64(none)1.fc34248.100:248.10-1.fc341161ae6945719a39systemd-0:248.10-1.fc34.x86_64

Test that the debug-shell service is not running  oval:ssg-test_service_not_running_debug-shell:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-obj_service_not_running_debug-shell:obj:1 of type systemdunitproperty_object
UnitProperty
^debug-shell\.(service|socket)$ActiveState

Test that the property LoadState from the service debug-shell is masked  oval:ssg-test_service_loadstate_is_masked_debug-shell:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-obj_service_loadstate_is_masked_debug-shell:obj:1 of type systemdunitproperty_object
UnitProperty
^debug-shell\.(service|socket)$LoadState
Verify that Interactive Boot is Disabledxccdf_org.ssgproject.content_rule_grub2_disable_interactive_boot medium

Verify that Interactive Boot is Disabled

Rule IDxccdf_org.ssgproject.content_rule_grub2_disable_interactive_boot
Result
pass
Multi-check ruleno
OVAL Definition IDoval:ssg-grub2_disable_interactive_boot:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  11, 12, 14, 15, 16, 18, 3, 5, DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS06.03, DSS06.06, 3.1.2, 3.4.5, CCI-000213, 164.308(a)(1)(ii)(B), 164.308(a)(7)(i), 164.308(a)(7)(ii)(A), 164.310(a)(1), 164.310(a)(2)(i), 164.310(a)(2)(ii), 164.310(a)(2)(iii), 164.310(b), 164.310(c), 164.310(d)(1), 164.310(d)(2)(iii), 4.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, A.6.1.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5, SC-2(1), CM-6(a), PR.AC-4, PR.AC-6, PR.PT-3, FIA_UAU.1, SRG-OS-000480-GPOS-00227

Description
Fedora systems support an "interactive boot" option that can be used to prevent services from being started. On a Fedora system, interactive boot can be enabled by providing a 1, yes, true, or on value to the systemd.confirm_spawn kernel argument in /etc/default/grub. Remove any instance of
systemd.confirm_spawn=(1|yes|true|on)
from the kernel arguments in that file to disable interactive boot. It is also required to change the runtime configuration, run:
/sbin/grubby --update-kernel=ALL --remove-args="systemd.confirm_spawn"
Rationale
Using interactive boot, the console user could disable auditing, firewalls, or other services, weakening system security.
OVAL test results details

Check systemd.confirm_spawn=(1|true|yes|on) not in GRUB_CMDLINE_LINUX  oval:ssg-test_grub2_disable_interactive_boot_grub_cmdline_linux:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-object_grub2_disable_interactive_boot_grub_cmdline_linux:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/default/grub^\s*GRUB_CMDLINE_LINUX=".*systemd.confirm_spawn=(?:1|yes|true|on).*$1

Check systemd.confirm_spawn=(1|true|yes|on) not in GRUB_CMDLINE_LINUX_DEFAULT  oval:ssg-test_grub2_disable_interactive_boot_grub_cmdline_linux_default:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-object_grub2_disable_interactive_boot_grub_cmdline_linux_default:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/default/grub^\s*GRUB_CMDLINE_LINUX_DEFAULT=".*systemd.confirm_spawn=(?:1|yes|true|on).*$1

Check for GRUB_DISABLE_RECOVERY=true in /etc/default/grub  oval:ssg-test_bootloader_disable_recovery_set_to_true:tst:1  true

Following items have been found on the system:
PathContent
/etc/default/grubGRUB_DISABLE_RECOVERY="true"
Require Authentication for Single User Modexccdf_org.ssgproject.content_rule_require_singleuser_auth medium

Require Authentication for Single User Mode

Rule IDxccdf_org.ssgproject.content_rule_require_singleuser_auth
Result
pass
Multi-check ruleno
OVAL Definition IDoval:ssg-require_singleuser_auth:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 14, 15, 16, 18, 3, 5, DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.06, DSS06.10, 3.1.1, 3.4.5, CCI-000213, 164.308(a)(1)(ii)(B), 164.308(a)(7)(i), 164.308(a)(7)(ii)(A), 164.310(a)(1), 164.310(a)(2)(i), 164.310(a)(2)(ii), 164.310(a)(2)(iii), 164.310(b), 164.310(c), 164.310(d)(1), 164.310(d)(2)(iii), 4.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, 0421, 0422, 0431, 0974, 1173, 1401, 1504, 1505, 1546, 1557, 1558, 1559, 1560, 1561, A.18.1.4, A.6.1.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.1, A.9.4.2, A.9.4.3, A.9.4.4, A.9.4.5, CIP-003-8 R5.1.1, CIP-003-8 R5.3, CIP-004-6 R2.2.3, CIP-004-6 R2.3, CIP-007-3 R5.1, CIP-007-3 R5.1.2, CIP-007-3 R5.2, CIP-007-3 R5.3.1, CIP-007-3 R5.3.2, CIP-007-3 R5.3.3, IA-2, AC-3, CM-6(a), PR.AC-1, PR.AC-4, PR.AC-6, PR.AC-7, PR.PT-3, FIA_UAU.1, SRG-OS-000080-GPOS-00048

Description
Single-user mode is intended as a system recovery method, providing a single user root access to the system by providing a boot option at startup. By default, no authentication is performed if single-user mode is selected.

By default, single-user mode is protected by requiring a password and is set in /usr/lib/systemd/system/rescue.service.
Rationale
This prevents attackers with physical access from trivially bypassing security on the machine and gaining root access. Such accesses are further prevented by configuring the bootloader password.
OVAL test results details

Tests that /usr/lib/systemd/systemd-sulogin-shell was not removed from the default systemd rescue.service to ensure that a password must be entered to access single user mode  oval:ssg-test_require_rescue_service:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/rescue.serviceExecStart=-/usr/lib/systemd/systemd-sulogin-shell rescue

Tests that the systemd rescue.service is in the runlevel1.target  oval:ssg-test_require_rescue_service_runlevel1:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/runlevel1.targetRequires=sysinit.target rescue.service

look for runlevel1.target in /etc/systemd/system  oval:ssg-test_no_custom_runlevel1_target:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_no_custom_runlevel1_target:obj:1 of type file_object
BehaviorsPathFilename
no value/etc/systemd/system^runlevel1.target$

look for rescue.service in /etc/systemd/system  oval:ssg-test_no_custom_rescue_service:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_no_custom_rescue_service:obj:1 of type file_object
BehaviorsPathFilename
no value/etc/systemd/system^rescue.service$
Prevent Login to Accounts With Empty Passwordxccdf_org.ssgproject.content_rule_no_empty_passwords high

Prevent Login to Accounts With Empty Password

Rule IDxccdf_org.ssgproject.content_rule_no_empty_passwords
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-no_empty_passwords:def:1
Time2024-12-29T17:33:55+01:00
Severityhigh
Identifiers and References

References:  1, 12, 13, 14, 15, 16, 18, 3, 5, 5.5.2, APO01.06, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.02, DSS06.03, DSS06.10, 3.1.1, 3.1.5, CCI-000366, 164.308(a)(1)(ii)(B), 164.308(a)(7)(i), 164.308(a)(7)(ii)(A), 164.310(a)(1), 164.310(a)(2)(i), 164.310(a)(2)(ii), 164.310(a)(2)(iii), 164.310(b), 164.310(c), 164.310(d)(1), 164.310(d)(2)(iii), 4.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, SR 1.1, SR 1.10, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 5.2, A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.13.1.1, A.13.1.3, A.13.2.1, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.18.1.4, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.1, A.9.4.2, A.9.4.3, A.9.4.4, A.9.4.5, IA-5(1)(a), IA-5(c), CM-6(a), PR.AC-1, PR.AC-4, PR.AC-6, PR.AC-7, PR.DS-5, FIA_UAU.1, Req-8.2.3, SRG-OS-000480-GPOS-00227

Description
If an account is configured for password authentication but does not have an assigned password, it may be possible to log into the account without authentication. Remove any instances of the nullok in /etc/pam.d/system-auth to prevent logins with empty passwords.
Rationale
If an account has an empty password, anyone could log in and run commands with the privileges of that account. Accounts with empty passwords should never be used in operational environments.
Warnings
warning  If the system relies on authselect tool to manage PAM settings, the remediation will also use authselect tool. However, if any manual modification was made in PAM files, the authselect integrity check will fail and the remediation will be aborted in order to preserve intentional changes. In this case, an informative message will be shown in the remediation report. Note that this rule is not applicable for systems running within a container. Having user with empty password within a container is not considered a risk, because it should not be possible to directly login into a container anyway.

Complexity:low
Disruption:medium
Strategy:configure
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

SYSTEM_AUTH="/etc/pam.d/system-auth"
PASSWORD_AUTH="/etc/pam.d/password-auth"

if [ -f /usr/bin/authselect ]; then
    if authselect check; then
        authselect enable-feature without-nullok
        authselect apply-changes
    else
        echo "
authselect integrity check failed. Remediation aborted!
This remediation could not be applied because the authselect profile is not intact.
It is not recommended to manually edit the PAM files when authselect is available
In cases where the default authselect profile does not cover a specific demand, a custom authselect profile is recommended."
        false
    fi
else
    sed --follow-symlinks -i 's/\<nullok\>//g' $SYSTEM_AUTH
    sed --follow-symlinks -i 's/\<nullok\>//g' $PASSWORD_AUTH
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:medium
Strategy:configure
- name: Check if system relies on authselect
  ansible.builtin.stat:
    path: /usr/bin/authselect
  register: result_authselect_present
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - CJIS-5.5.2
    - NIST-800-171-3.1.1
    - NIST-800-171-3.1.5
    - NIST-800-53-CM-6(a)
    - NIST-800-53-IA-5(1)(a)
    - NIST-800-53-IA-5(c)
    - PCI-DSS-Req-8.2.3
    - configure_strategy
    - high_severity
    - low_complexity
    - medium_disruption
    - no_empty_passwords
    - no_reboot_needed

- name: Check integrity of authselect current profile
  ansible.builtin.command:
    cmd: authselect check
  register: result_authselect_check_cmd
  changed_when: false
  ignore_errors: true
  when:
    - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
    - result_authselect_present.stat.exists
  tags:
    - CJIS-5.5.2
    - NIST-800-171-3.1.1
    - NIST-800-171-3.1.5
    - NIST-800-53-CM-6(a)
    - NIST-800-53-IA-5(1)(a)
    - NIST-800-53-IA-5(c)
    - PCI-DSS-Req-8.2.3
    - configure_strategy
    - high_severity
    - low_complexity
    - medium_disruption
    - no_empty_passwords
    - no_reboot_needed

- name: Get authselect current features
  ansible.builtin.shell:
    cmd: authselect current | tail -n+3 | awk '{ print $2 }'
  register: result_authselect_features
  changed_when: false
  when:
    - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
    - result_authselect_present.stat.exists
    - result_authselect_check_cmd is success
  tags:
    - CJIS-5.5.2
    - NIST-800-171-3.1.1
    - NIST-800-171-3.1.5
    - NIST-800-53-CM-6(a)
    - NIST-800-53-IA-5(1)(a)
    - NIST-800-53-IA-5(c)
    - PCI-DSS-Req-8.2.3
    - configure_strategy
    - high_severity
    - low_complexity
    - medium_disruption
    - no_empty_passwords
    - no_reboot_needed

- name: Ensure nullok property is absent via authselect tool
  ansible.builtin.command:
    cmd: authselect enable-feature without-nullok
  register: result_authselect_cmd
  when:
    - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
    - result_authselect_present.stat.exists
    - result_authselect_check_cmd is success
    - result_authselect_features.stdout is not search("without-nullok")
  tags:
    - CJIS-5.5.2
    - NIST-800-171-3.1.1
    - NIST-800-171-3.1.5
    - NIST-800-53-CM-6(a)
    - NIST-800-53-IA-5(1)(a)
    - NIST-800-53-IA-5(c)
    - PCI-DSS-Req-8.2.3
    - configure_strategy
    - high_severity
    - low_complexity
    - medium_disruption
    - no_empty_passwords
    - no_reboot_needed

- name: Informative message based on the authselect integrity check result
  ansible.builtin.assert:
    that:
      - result_authselect_check_cmd is success
    fail_msg:
      - authselect integrity check failed. Remediation aborted!
      - This remediation could not be applied because the authselect profile is not
        intact.
      - It is not recommended to manually edit the PAM files when authselect is available
      - In cases where the default authselect profile does not cover a specific demand,
        a custom authselect profile is recommended.
    success_msg:
      - authselect integrity check passed
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - CJIS-5.5.2
    - NIST-800-171-3.1.1
    - NIST-800-171-3.1.5
    - NIST-800-53-CM-6(a)
    - NIST-800-53-IA-5(1)(a)
    - NIST-800-53-IA-5(c)
    - PCI-DSS-Req-8.2.3
    - configure_strategy
    - high_severity
    - low_complexity
    - medium_disruption
    - no_empty_passwords
    - no_reboot_needed

- name: Ensure nullok property is absent by directly editing pam files
  replace:
    dest: '{{ item }}'
    regexp: nullok
  loop:
    - /etc/pam.d/system-auth
    - /etc/pam.d/password-auth
  when:
    - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
    - not result_authselect_present.stat.exists
  tags:
    - CJIS-5.5.2
    - NIST-800-171-3.1.1
    - NIST-800-171-3.1.5
    - NIST-800-53-CM-6(a)
    - NIST-800-53-IA-5(1)(a)
    - NIST-800-53-IA-5(c)
    - PCI-DSS-Req-8.2.3
    - configure_strategy
    - high_severity
    - low_complexity
    - medium_disruption
    - no_empty_passwords
    - no_reboot_needed

---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,%23%20Generated%20by%20authselect%20on%20Sat%20Oct%2027%2014%3A59%3A36%202018%0A%23%20Do%20not%20modify%20this%20file%20manually.%0A%0Aauth%20%20%20%20%20%20%20%20required%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_env.so%0Aauth%20%20%20%20%20%20%20%20required%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_faildelay.so%20delay%3D2000000%0Aauth%20%20%20%20%20%20%20%20sufficient%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_fprintd.so%0Aauth%20%20%20%20%20%20%20%20%5Bdefault%3D1%20ignore%3Dignore%20success%3Dok%5D%20%20%20%20%20%20%20%20%20pam_succeed_if.so%20uid%20%3E%3D%201000%20quiet%0Aauth%20%20%20%20%20%20%20%20%5Bdefault%3D1%20ignore%3Dignore%20success%3Dok%5D%20%20%20%20%20%20%20%20%20pam_localuser.so%0Aauth%20%20%20%20%20%20%20%20sufficient%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_unix.so%20try_first_pass%0Aauth%20%20%20%20%20%20%20%20requisite%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_succeed_if.so%20uid%20%3E%3D%201000%20quiet_success%0Aauth%20%20%20%20%20%20%20%20sufficient%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_sss.so%20forward_pass%0Aauth%20%20%20%20%20%20%20%20required%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_deny.so%0A%0Aaccount%20%20%20%20%20required%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_unix.so%0Aaccount%20%20%20%20%20sufficient%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_localuser.so%0Aaccount%20%20%20%20%20sufficient%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_succeed_if.so%20uid%20%3C%201000%20quiet%0Aaccount%20%20%20%20%20%5Bdefault%3Dbad%20success%3Dok%20user_unknown%3Dignore%5D%20pam_sss.so%0Aaccount%20%20%20%20%20required%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_permit.so%0A%0Apassword%20%20%20%20requisite%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_pwquality.so%20try_first_pass%20local_users_only%0Apassword%20%20%20%20sufficient%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_unix.so%20sha512%20shadow%20try_first_pass%20use_authtok%0Apassword%20%20%20%20sufficient%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_sss.so%20use_authtok%0Apassword%20%20%20%20required%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_deny.so%0A%0Asession%20%20%20%20%20optional%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_keyinit.so%20revoke%0Asession%20%20%20%20%20required%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_limits.so%0A-session%20%20%20%20optional%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_systemd.so%0Asession%20%20%20%20%20%5Bsuccess%3D1%20default%3Dignore%5D%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_succeed_if.so%20service%20in%20crond%20quiet%20use_uid%0Asession%20%20%20%20%20required%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_unix.so%0Asession%20%20%20%20%20optional%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_sss.so%0A
        mode: 0644
        path: /etc/pam.d/password-auth
        overwrite: true
      - contents:
          source: data:,%23%20Generated%20by%20authselect%20on%20Sat%20Oct%2027%2014%3A59%3A36%202018%0A%23%20Do%20not%20modify%20this%20file%20manually.%0A%0Aauth%20%20%20%20%20%20%20%20required%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_env.so%0Aauth%20%20%20%20%20%20%20%20required%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_faildelay.so%20delay%3D2000000%0Aauth%20%20%20%20%20%20%20%20sufficient%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_fprintd.so%0Aauth%20%20%20%20%20%20%20%20%5Bdefault%3D1%20ignore%3Dignore%20success%3Dok%5D%20%20%20%20%20%20%20%20%20pam_succeed_if.so%20uid%20%3E%3D%201000%20quiet%0Aauth%20%20%20%20%20%20%20%20%5Bdefault%3D1%20ignore%3Dignore%20success%3Dok%5D%20%20%20%20%20%20%20%20%20pam_localuser.so%0Aauth%20%20%20%20%20%20%20%20sufficient%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_unix.so%20try_first_pass%0Aauth%20%20%20%20%20%20%20%20requisite%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_succeed_if.so%20uid%20%3E%3D%201000%20quiet_success%0Aauth%20%20%20%20%20%20%20%20sufficient%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_sss.so%20forward_pass%0Aauth%20%20%20%20%20%20%20%20required%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_deny.so%0A%0Aaccount%20%20%20%20%20required%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_unix.so%0Aaccount%20%20%20%20%20sufficient%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_localuser.so%0Aaccount%20%20%20%20%20sufficient%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_succeed_if.so%20uid%20%3C%201000%20quiet%0Aaccount%20%20%20%20%20%5Bdefault%3Dbad%20success%3Dok%20user_unknown%3Dignore%5D%20pam_sss.so%0Aaccount%20%20%20%20%20required%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_permit.so%0A%0Apassword%20%20%20%20requisite%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_pwquality.so%20try_first_pass%20local_users_only%0Apassword%20%20%20%20sufficient%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_unix.so%20sha512%20shadow%20try_first_pass%20use_authtok%0Apassword%20%20%20%20sufficient%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_sss.so%20use_authtok%0Apassword%20%20%20%20required%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_deny.so%0A%0Asession%20%20%20%20%20optional%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_keyinit.so%20revoke%0Asession%20%20%20%20%20required%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_limits.so%0A-session%20%20%20%20optional%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_systemd.so%0Asession%20%20%20%20%20%5Bsuccess%3D1%20default%3Dignore%5D%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_succeed_if.so%20service%20in%20crond%20quiet%20use_uid%0Asession%20%20%20%20%20required%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_unix.so%0Asession%20%20%20%20%20optional%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_sss.so%0A
        mode: 0644
        path: /etc/pam.d/system-auth
        overwrite: true
OVAL test results details

make sure nullok is not used in /etc/pam.d/system-auth  oval:ssg-test_no_empty_passwords:tst:1  false

Following items have been found on the system:
PathContent
/etc/pam.d/system-auth auth required pam_env.so auth required pam_faildelay.so delay=2000000 auth sufficient pam_fprintd.so auth [default=1 ignore=ignore success=ok] pam_usertype.so isregular auth [default=1 ignore=ignore success=ok] pam_localuser.so auth sufficient pam_unix.so nullok try_first_pass auth [default=1 ignore=ignore success=ok] pam_usertype.so isregular auth sufficient pam_sss.so forward_pass auth required pam_deny.so account required pam_unix.so account sufficient pam_localuser.so account sufficient pam_usertype.so issystem account [default=bad success=ok user_unknown=ignore] pam_sss.so account required pam_permit.so password requisite pam_pwquality.so try_first_pass local_users_only password sufficient pam_unix.so sha512 shadow nullok try_first_pass use_authtok
Set Interactive Session Timeoutxccdf_org.ssgproject.content_rule_accounts_tmout medium

Set Interactive Session Timeout

Rule IDxccdf_org.ssgproject.content_rule_accounts_tmout
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-accounts_tmout:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  BP28(R29), 1, 12, 15, 16, DSS05.04, DSS05.10, DSS06.10, 3.1.11, CCI-000057, CCI-001133, CCI-002361, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, SR 1.1, SR 1.10, SR 1.2, SR 1.5, SR 1.7, SR 1.8, SR 1.9, A.18.1.4, A.9.2.1, A.9.2.4, A.9.3.1, A.9.4.2, A.9.4.3, CIP-004-6 R2.2.3, CIP-007-3 R5.1, CIP-007-3 R5.2, CIP-007-3 R5.3.1, CIP-007-3 R5.3.2, CIP-007-3 R5.3.3, AC-12, SC-10, AC-2(5), CM-6(a), PR.AC-7, FMT_MOF_EXT.1, SRG-OS-000163-GPOS-00072, SRG-OS-000029-GPOS-00010, SRG-OS-000163-VMM-000700, SRG-OS-000279-VMM-001010

Description
Setting the TMOUT option in /etc/profile ensures that all user sessions will terminate based on inactivity. The TMOUT setting in a file loaded by /etc/profile, e.g. /etc/profile.d/tmout.sh should read as follows:
TMOUT=600
Rationale
Terminating an idle session within a short time period reduces the window of opportunity for unauthorized personnel to take control of a management session enabled on the console or console port that has been left unattended.

# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

var_accounts_tmout='600'


# if 0, no occurence of tmout found, if 1, occurence found
tmout_found=0

for f in /etc/profile /etc/profile.d/*.sh; do
    if grep --silent '^\s*TMOUT' $f; then
        sed -i -E "s/^(\s*)TMOUT\s*=\s*(\w|\$)*(.*)$/\1TMOUT=$var_accounts_tmout\3/g" $f
        tmout_found=1
    fi
done

if [ $tmout_found -eq 0 ]; then
        echo -e "\n# Set TMOUT to $var_accounts_tmout per security requirements" >> /etc/profile.d/tmout.sh
        echo "TMOUT=$var_accounts_tmout" >> /etc/profile.d/tmout.sh
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: XCCDF Value var_accounts_tmout # promote to variable
  set_fact:
    var_accounts_tmout: !!str 600
  tags:
    - always

- name: Set Interactive Session Timeout
  block:

    - name: Check for duplicate values
      lineinfile:
        path: /etc/profile.d/tmout.sh
        create: false
        regexp: ^\s*TMOUT=
        state: absent
      check_mode: true
      changed_when: false
      register: dupes

    - name: Deduplicate values from /etc/profile.d/tmout.sh
      lineinfile:
        path: /etc/profile.d/tmout.sh
        create: false
        regexp: ^\s*TMOUT=
        state: absent
      when: dupes.found is defined and dupes.found > 1

    - name: Insert correct line to /etc/profile.d/tmout.sh
      lineinfile:
        path: /etc/profile.d/tmout.sh
        create: true
        regexp: ^\s*TMOUT=
        line: TMOUT={{ var_accounts_tmout }}
        state: present
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-171-3.1.11
    - NIST-800-53-AC-12
    - NIST-800-53-AC-2(5)
    - NIST-800-53-CM-6(a)
    - NIST-800-53-SC-10
    - accounts_tmout
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

TMOUT in /etc/profile  oval:ssg-test_etc_profile_tmout:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_etc_profile_tmout:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/profile^[\s]*TMOUT=([\w$]+).*$1

TMOUT in /etc/profile.d/*.sh  oval:ssg-test_etc_profiled_tmout:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_etc_profiled_tmout:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/etc/profile.d^.*\.sh$^[\s]*TMOUT=([\w$]+).*$1
Record Events that Modify the System's Discretionary Access Controls - chmodxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_chmod medium

Record Events that Modify the System's Discretionary Access Controls - chmod

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_chmod
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_dac_modification_chmod:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, 5.4.1.1, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000126, CCI-000130, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.5.5, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000064-GPOS-00033, SRG-OS-000466-GPOS-00210, SRG-OS-000458-GPOS-00203, SRG-OS-000458-VMM-001810, SRG-OS-000474-VMM-001940

Description
At a minimum, the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S chmod -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S chmod -F auid>=1000 -F auid!=unset -F key=perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S chmod -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S chmod -F auid>=1000 -F auid!=unset -F key=perm_mod
Rationale
The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="chmod"
	KEY="perm_mod"
	SYSCALL_GROUPING="chmod fchmod fchmodat"

	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_chmod
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit chmod tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_chmod
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for chmod for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - chmod
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat

    - name: Check existence of chmod in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
      set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - chmod
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat

    - name: Check existence of chmod in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_chmod
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for chmod for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - chmod
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat

    - name: Check existence of chmod in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
      set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - chmod
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat

    - name: Check existence of chmod in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_chmod
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit chmod  oval:ssg-test_32bit_ardm_chmod_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_chmod_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+chmod[\s]+|([\s]+|[,])chmod([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit chmod  oval:ssg-test_64bit_ardm_chmod_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_chmod_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+chmod[\s]+|([\s]+|[,])chmod([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit chmod  oval:ssg-test_32bit_ardm_chmod_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_chmod_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+chmod[\s]+|([\s]+|[,])chmod([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit chmod  oval:ssg-test_64bit_ardm_chmod_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_chmod_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+chmod[\s]+|([\s]+|[,])chmod([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Record Events that Modify the System's Discretionary Access Controls - chownxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_chown medium

Record Events that Modify the System's Discretionary Access Controls - chown

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_chown
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_dac_modification_chown:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, 5.4.1.1, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000126, CCI-000130, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.5.5, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000064-GPOS-00033, SRG-OS-000466-GPOS-00210, SRG-OS-000458-GPOS-00203, SRG-OS-000474-GPOS-00219, SRG-OS-000458-VMM-001810, SRG-OS-000474-VMM-001940

Description
At a minimum, the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S chown -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S chown -F auid>=1000 -F auid!=unset -F key=perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S chown -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S chown -F auid>=1000 -F auid!=unset -F key=perm_mod
Rationale
The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="chown"
	KEY="perm_mod"
	SYSCALL_GROUPING="chown fchown fchownat lchown"

	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_chown
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit chown tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_chown
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for chown for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - chown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of chown in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
      set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - chown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of chown in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_chown
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for chown for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - chown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of chown in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
      set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - chown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of chown in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_chown
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit chown  oval:ssg-test_32bit_ardm_chown_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_chown_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+chown[\s]+|([\s]+|[,])chown([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit chown  oval:ssg-test_64bit_ardm_chown_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_chown_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+chown[\s]+|([\s]+|[,])chown([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit chown  oval:ssg-test_32bit_ardm_chown_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_chown_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+chown[\s]+|([\s]+|[,])chown([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit chown  oval:ssg-test_64bit_ardm_chown_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_chown_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+chown[\s]+|([\s]+|[,])chown([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Record Events that Modify the System's Discretionary Access Controls - fchmodxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_fchmod medium

Record Events that Modify the System's Discretionary Access Controls - fchmod

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_fchmod
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_dac_modification_fchmod:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, 5.4.1.1, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000126, CCI-000130, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.5.5, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000064-GPOS-00033, SRG-OS-000466-GPOS-00210, SRG-OS-000458-GPOS-00203, SRG-OS-000458-VMM-001810, SRG-OS-000474-VMM-001940

Description
At a minimum, the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S fchmod -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fchmod -F auid>=1000 -F auid!=unset -F key=perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S fchmod -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fchmod -F auid>=1000 -F auid!=unset -F key=perm_mod
Rationale
The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="fchmod"
	KEY="perm_mod"
	SYSCALL_GROUPING="chmod fchmod fchmodat"

	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_fchmod
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit fchmod tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_fchmod
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fchmod for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchmod
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat

    - name: Check existence of fchmod in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
      set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchmod
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat

    - name: Check existence of fchmod in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_fchmod
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fchmod for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchmod
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat

    - name: Check existence of fchmod in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
      set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchmod
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat

    - name: Check existence of fchmod in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_fchmod
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit fchmod  oval:ssg-test_32bit_ardm_fchmod_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_fchmod_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchmod[\s]+|([\s]+|[,])fchmod([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit fchmod  oval:ssg-test_64bit_ardm_fchmod_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_fchmod_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchmod[\s]+|([\s]+|[,])fchmod([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit fchmod  oval:ssg-test_32bit_ardm_fchmod_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_fchmod_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchmod[\s]+|([\s]+|[,])fchmod([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit fchmod  oval:ssg-test_64bit_ardm_fchmod_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_fchmod_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchmod[\s]+|([\s]+|[,])fchmod([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Record Events that Modify the System's Discretionary Access Controls - fchmodatxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_fchmodat medium

Record Events that Modify the System's Discretionary Access Controls - fchmodat

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_fchmodat
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_dac_modification_fchmodat:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, 5.4.1.1, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000126, CCI-000130, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.5.5, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000064-GPOS-00033, SRG-OS-000466-GPOS-00210, SRG-OS-000458-GPOS-00203, SRG-OS-000458-VMM-001810, SRG-OS-000474-VMM-001940

Description
At a minimum, the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S fchmodat -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fchmodat -F auid>=1000 -F auid!=unset -F key=perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S fchmodat -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fchmodat -F auid>=1000 -F auid!=unset -F key=perm_mod
Rationale
The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="fchmodat"
	KEY="perm_mod"
	SYSCALL_GROUPING="chmod fchmod fchmodat"

	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_fchmodat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit fchmodat tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_fchmodat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fchmodat for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchmodat
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat

    - name: Check existence of fchmodat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
      set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchmodat
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat

    - name: Check existence of fchmodat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_fchmodat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fchmodat for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchmodat
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat

    - name: Check existence of fchmodat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
      set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchmodat
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat

    - name: Check existence of fchmodat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_fchmodat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit fchmodat  oval:ssg-test_32bit_ardm_fchmodat_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_fchmodat_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchmodat[\s]+|([\s]+|[,])fchmodat([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit fchmodat  oval:ssg-test_64bit_ardm_fchmodat_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_fchmodat_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchmodat[\s]+|([\s]+|[,])fchmodat([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit fchmodat  oval:ssg-test_32bit_ardm_fchmodat_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_fchmodat_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchmodat[\s]+|([\s]+|[,])fchmodat([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit fchmodat  oval:ssg-test_64bit_ardm_fchmodat_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_fchmodat_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchmodat[\s]+|([\s]+|[,])fchmodat([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Record Events that Modify the System's Discretionary Access Controls - fchownxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_fchown medium

Record Events that Modify the System's Discretionary Access Controls - fchown

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_fchown
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_dac_modification_fchown:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, 5.4.1.1, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000126, CCI-000130, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.5.5, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000064-GPOS-00033, SRG-OS-000466-GPOS-00210, SRG-OS-000458-GPOS-00203, SRG-OS-000474-GPOS-00219, SRG-OS-000458-VMM-001810, SRG-OS-000474-VMM-001940

Description
At a minimum, the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S fchown -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fchown -F auid>=1000 -F auid!=unset -F key=perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S fchown -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fchown -F auid>=1000 -F auid!=unset -F key=perm_mod
Rationale
The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="fchown"
	KEY="perm_mod"
	SYSCALL_GROUPING="chown fchown fchownat lchown"

	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_fchown
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit fchown tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_fchown
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fchown for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of fchown in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
      set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of fchown in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_fchown
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fchown for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of fchown in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
      set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of fchown in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_fchown
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit fchown  oval:ssg-test_32bit_ardm_fchown_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_fchown_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchown[\s]+|([\s]+|[,])fchown([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit fchown  oval:ssg-test_64bit_ardm_fchown_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_fchown_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchown[\s]+|([\s]+|[,])fchown([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit fchown  oval:ssg-test_32bit_ardm_fchown_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_fchown_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchown[\s]+|([\s]+|[,])fchown([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit fchown  oval:ssg-test_64bit_ardm_fchown_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_fchown_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchown[\s]+|([\s]+|[,])fchown([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Record Events that Modify the System's Discretionary Access Controls - fchownatxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_fchownat medium

Record Events that Modify the System's Discretionary Access Controls - fchownat

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_fchownat
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_dac_modification_fchownat:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, 5.4.1.1, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000126, CCI-000130, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.5.5, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000064-GPOS-00033, SRG-OS-000466-GPOS-00210, SRG-OS-000458-GPOS-00203, SRG-OS-000474-GPOS-00219, SRG-OS-000458-VMM-001810, SRG-OS-000474-VMM-001940

Description
At a minimum, the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S fchownat -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fchownat -F auid>=1000 -F auid!=unset -F key=perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S fchownat -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fchownat -F auid>=1000 -F auid!=unset -F key=perm_mod
Rationale
The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="fchownat"
	KEY="perm_mod"
	SYSCALL_GROUPING="chown fchown fchownat lchown"

	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_fchownat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit fchownat tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_fchownat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fchownat for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchownat
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of fchownat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
      set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchownat
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of fchownat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_fchownat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fchownat for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchownat
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of fchownat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
      set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchownat
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of fchownat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_fchownat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit fchownat  oval:ssg-test_32bit_ardm_fchownat_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_fchownat_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchownat[\s]+|([\s]+|[,])fchownat([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit fchownat  oval:ssg-test_64bit_ardm_fchownat_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_fchownat_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchownat[\s]+|([\s]+|[,])fchownat([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit fchownat  oval:ssg-test_32bit_ardm_fchownat_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_fchownat_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchownat[\s]+|([\s]+|[,])fchownat([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit fchownat  oval:ssg-test_64bit_ardm_fchownat_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_fchownat_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchownat[\s]+|([\s]+|[,])fchownat([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Record Events that Modify the System's Discretionary Access Controls - fremovexattrxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_fremovexattr medium

Record Events that Modify the System's Discretionary Access Controls - fremovexattr

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_fremovexattr
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_dac_modification_fremovexattr:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, 5.4.1.1, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000130, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.5.5, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000458-GPOS-00203, SRG-OS-000462-GPOS-00206, SRG-OS-000463-GPOS-00207, SRG-OS-000471-GPOS-00215, SRG-OS-000474-GPOS-00219, SRG-OS-000466-GPOS-00210, SRG-OS-000064-GPOS-00033, SRG-OS-000458-VMM-001810, SRG-OS-000474-VMM-001940

Description
At a minimum, the audit system should collect file permission changes for all users and root.

If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S fremovexattr -F auid>=1000 -F auid!=unset -F key=perm_mod


If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fremovexattr -F auid>=1000 -F auid!=unset -F key=perm_mod


If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S fremovexattr -F auid>=1000 -F auid!=unset -F key=perm_mod


If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fremovexattr -F auid>=1000 -F auid!=unset -F key=perm_mod
Rationale
The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="fremovexattr"
	KEY="perm_mod"
	SYSCALL_GROUPING="fremovexattr lremovexattr removexattr fsetxattr lsetxattr setxattr"

	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_fremovexattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit fremovexattr tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_fremovexattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fremovexattr for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fremovexattr
        syscall_grouping:
          - fremovexattr
          - lremovexattr
          - removexattr
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of fremovexattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
      set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fremovexattr
        syscall_grouping:
          - fremovexattr
          - lremovexattr
          - removexattr
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of fremovexattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_fremovexattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fremovexattr for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fremovexattr
        syscall_grouping:
          - fremovexattr
          - lremovexattr
          - removexattr
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of fremovexattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
      set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fremovexattr
        syscall_grouping:
          - fremovexattr
          - lremovexattr
          - removexattr
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of fremovexattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_fremovexattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit fremovexattr  oval:ssg-test_32bit_ardm_fremovexattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_fremovexattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fremovexattr[\s]+|([\s]+|[,])fremovexattr([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit fremovexattr  oval:ssg-test_64bit_ardm_fremovexattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_fremovexattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fremovexattr[\s]+|([\s]+|[,])fremovexattr([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit fremovexattr  oval:ssg-test_32bit_ardm_fremovexattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_fremovexattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fremovexattr[\s]+|([\s]+|[,])fremovexattr([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit fremovexattr  oval:ssg-test_64bit_ardm_fremovexattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_fremovexattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fremovexattr[\s]+|([\s]+|[,])fremovexattr([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Record Events that Modify the System's Discretionary Access Controls - fsetxattrxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_fsetxattr medium

Record Events that Modify the System's Discretionary Access Controls - fsetxattr

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_fsetxattr
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_dac_modification_fsetxattr:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, 5.4.1.1, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000126, CCI-000130, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.5.5, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000458-GPOS-00203, SRG-OS-000462-GPOS-00206, SRG-OS-000463-GPOS-00207, SRG-OS-000468-GPOS-00212, SRG-OS-000471-GPOS-00215, SRG-OS-000474-GPOS-00219, SRG-OS-000064-GPOS-00033, SRG-OS-000458-VMM-001810, SRG-OS-000474-VMM-001940

Description
At a minimum, the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S fsetxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fsetxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S fsetxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fsetxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
Rationale
The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="fsetxattr"
	KEY="perm_mod"
	SYSCALL_GROUPING="fremovexattr lremovexattr removexattr fsetxattr lsetxattr setxattr"

	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_fsetxattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit fsetxattr tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_fsetxattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fsetxattr for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fsetxattr
        syscall_grouping:
          - fremovexattr
          - lremovexattr
          - removexattr
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of fsetxattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
      set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fsetxattr
        syscall_grouping:
          - fremovexattr
          - lremovexattr
          - removexattr
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of fsetxattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_fsetxattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fsetxattr for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fsetxattr
        syscall_grouping:
          - fremovexattr
          - lremovexattr
          - removexattr
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of fsetxattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
      set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fsetxattr
        syscall_grouping:
          - fremovexattr
          - lremovexattr
          - removexattr
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of fsetxattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_fsetxattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit fsetxattr  oval:ssg-test_32bit_ardm_fsetxattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_fsetxattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fsetxattr[\s]+|([\s]+|[,])fsetxattr([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit fsetxattr  oval:ssg-test_64bit_ardm_fsetxattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_fsetxattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fsetxattr[\s]+|([\s]+|[,])fsetxattr([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit fsetxattr  oval:ssg-test_32bit_ardm_fsetxattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_fsetxattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fsetxattr[\s]+|([\s]+|[,])fsetxattr([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit fsetxattr  oval:ssg-test_64bit_ardm_fsetxattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_fsetxattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fsetxattr[\s]+|([\s]+|[,])fsetxattr([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Record Events that Modify the System's Discretionary Access Controls - lchownxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_lchown medium

Record Events that Modify the System's Discretionary Access Controls - lchown

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_lchown
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_dac_modification_lchown:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, 5.4.1.1, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000126, CCI-000130, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.5.5, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000064-GPOS-00033, SRG-OS-000466-GPOS-00210, SRG-OS-000458-GPOS-00203, SRG-OS-000474-GPOS-00219, SRG-OS-000458-VMM-001810, SRG-OS-000474-VMM-001940

Description
At a minimum, the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S lchown -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S lchown -F auid>=1000 -F auid!=unset -F key=perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S lchown -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S lchown -F auid>=1000 -F auid!=unset -F key=perm_mod
Rationale
The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="lchown"
	KEY="perm_mod"
	SYSCALL_GROUPING="chown fchown fchownat lchown"

	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_lchown
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit lchown tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_lchown
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for lchown for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lchown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of lchown in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
      set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lchown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of lchown in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_lchown
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for lchown for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lchown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of lchown in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
      set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lchown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of lchown in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_lchown
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit lchown  oval:ssg-test_32bit_ardm_lchown_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_lchown_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+lchown[\s]+|([\s]+|[,])lchown([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit lchown  oval:ssg-test_64bit_ardm_lchown_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_lchown_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+lchown[\s]+|([\s]+|[,])lchown([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit lchown  oval:ssg-test_32bit_ardm_lchown_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_lchown_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+lchown[\s]+|([\s]+|[,])lchown([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit lchown  oval:ssg-test_64bit_ardm_lchown_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_lchown_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+lchown[\s]+|([\s]+|[,])lchown([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Record Events that Modify the System's Discretionary Access Controls - lremovexattrxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_lremovexattr medium

Record Events that Modify the System's Discretionary Access Controls - lremovexattr

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_lremovexattr
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_dac_modification_lremovexattr:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, 5.4.1.1, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000130, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.5.5, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000458-GPOS-00203, SRG-OS-000462-GPOS-00206, SRG-OS-000463-GPOS-00207, SRG-OS-000468-GPOS-00212, SRG-OS-000471-GPOS-00215, SRG-OS-000474-GPOS-00219, SRG-OS-000466-GPOS-00210, SRG-OS-000064-GPOS-00033, SRG-OS-000458-VMM-001810, SRG-OS-000474-VMM-001940

Description
At a minimum, the audit system should collect file permission changes for all users and root.

If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S lremovexattr -F auid>=1000 -F auid!=unset -F key=perm_mod


If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S lremovexattr -F auid>=1000 -F auid!=unset -F key=perm_mod


If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S lremovexattr -F auid>=1000 -F auid!=unset -F key=perm_mod


If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S lremovexattr -F auid>=1000 -F auid!=unset -F key=perm_mod
Rationale
The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="lremovexattr"
	KEY="perm_mod"
	SYSCALL_GROUPING="fremovexattr lremovexattr removexattr fsetxattr lsetxattr setxattr"

	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_lremovexattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit lremovexattr tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_lremovexattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for lremovexattr for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lremovexattr
        syscall_grouping:
          - fremovexattr
          - lremovexattr
          - removexattr
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of lremovexattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
      set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lremovexattr
        syscall_grouping:
          - fremovexattr
          - lremovexattr
          - removexattr
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of lremovexattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_lremovexattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for lremovexattr for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lremovexattr
        syscall_grouping:
          - fremovexattr
          - lremovexattr
          - removexattr
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of lremovexattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
      set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lremovexattr
        syscall_grouping:
          - fremovexattr
          - lremovexattr
          - removexattr
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of lremovexattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_lremovexattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit lremovexattr  oval:ssg-test_32bit_ardm_lremovexattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_lremovexattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+lremovexattr[\s]+|([\s]+|[,])lremovexattr([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit lremovexattr  oval:ssg-test_64bit_ardm_lremovexattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_lremovexattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+lremovexattr[\s]+|([\s]+|[,])lremovexattr([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit lremovexattr  oval:ssg-test_32bit_ardm_lremovexattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_lremovexattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+lremovexattr[\s]+|([\s]+|[,])lremovexattr([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit lremovexattr  oval:ssg-test_64bit_ardm_lremovexattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_lremovexattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+lremovexattr[\s]+|([\s]+|[,])lremovexattr([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Record Events that Modify the System's Discretionary Access Controls - lsetxattrxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_lsetxattr medium

Record Events that Modify the System's Discretionary Access Controls - lsetxattr

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_lsetxattr
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_dac_modification_lsetxattr:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, 5.4.1.1, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000126, CCI-000130, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.5.5, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000458-GPOS-00203, SRG-OS-000462-GPOS-00206, SRG-OS-000463-GPOS-00207, SRG-OS-000468-GPOS-00212, SRG-OS-000471-GPOS-00215, SRG-OS-000474-GPOS-00219, SRG-OS-000064-GPOS-00033, SRG-OS-000458-VMM-001810, SRG-OS-000474-VMM-001940

Description
At a minimum, the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S lsetxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S lsetxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S lsetxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S lsetxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
Rationale
The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="lsetxattr"
	KEY="perm_mod"
	SYSCALL_GROUPING="fremovexattr lremovexattr removexattr fsetxattr lsetxattr setxattr"

	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_lsetxattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit lsetxattr tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_lsetxattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for lsetxattr for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lsetxattr
        syscall_grouping:
          - fremovexattr
          - lremovexattr
          - removexattr
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of lsetxattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
      set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lsetxattr
        syscall_grouping:
          - fremovexattr
          - lremovexattr
          - removexattr
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of lsetxattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_lsetxattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for lsetxattr for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lsetxattr
        syscall_grouping:
          - fremovexattr
          - lremovexattr
          - removexattr
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of lsetxattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
      set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lsetxattr
        syscall_grouping:
          - fremovexattr
          - lremovexattr
          - removexattr
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of lsetxattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_lsetxattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit lsetxattr  oval:ssg-test_32bit_ardm_lsetxattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_lsetxattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+lsetxattr[\s]+|([\s]+|[,])lsetxattr([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit lsetxattr  oval:ssg-test_64bit_ardm_lsetxattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_lsetxattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+lsetxattr[\s]+|([\s]+|[,])lsetxattr([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit lsetxattr  oval:ssg-test_32bit_ardm_lsetxattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_lsetxattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+lsetxattr[\s]+|([\s]+|[,])lsetxattr([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit lsetxattr  oval:ssg-test_64bit_ardm_lsetxattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_lsetxattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+lsetxattr[\s]+|([\s]+|[,])lsetxattr([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Record Events that Modify the System's Discretionary Access Controls - removexattrxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_removexattr medium

Record Events that Modify the System's Discretionary Access Controls - removexattr

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_removexattr
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_dac_modification_removexattr:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, 5.4.1.1, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000130, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.5.5, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000458-GPOS-00203, SRG-OS-000462-GPOS-00206, SRG-OS-000463-GPOS-00207, SRG-OS-000468-GPOS-00212, SRG-OS-000471-GPOS-00215, SRG-OS-000474-GPOS-00219, SRG-OS-000466-GPOS-00210, SRG-OS-000064-GPOS-00033, SRG-OS-000458-VMM-001810, SRG-OS-000474-VMM-001940

Description
At a minimum, the audit system should collect file permission changes for all users and root.

If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S removexattr -F auid>=1000 -F auid!=unset -F key=perm_mod


If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S removexattr -F auid>=1000 -F auid!=unset -F key=perm_mod


If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S removexattr -F auid>=1000 -F auid!=unset -F key=perm_mod


If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S removexattr -F auid>=1000 -F auid!=unset -F key=perm_mod
Rationale
The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="removexattr"
	KEY="perm_mod"
	SYSCALL_GROUPING="fremovexattr lremovexattr removexattr fsetxattr lsetxattr setxattr"

	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_removexattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit removexattr tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_removexattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for removexattr for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - removexattr
        syscall_grouping:
          - fremovexattr
          - lremovexattr
          - removexattr
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of removexattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
      set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - removexattr
        syscall_grouping:
          - fremovexattr
          - lremovexattr
          - removexattr
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of removexattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_removexattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for removexattr for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - removexattr
        syscall_grouping:
          - fremovexattr
          - lremovexattr
          - removexattr
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of removexattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
      set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - removexattr
        syscall_grouping:
          - fremovexattr
          - lremovexattr
          - removexattr
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of removexattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_removexattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit removexattr  oval:ssg-test_32bit_ardm_removexattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_removexattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+removexattr[\s]+|([\s]+|[,])removexattr([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit removexattr  oval:ssg-test_64bit_ardm_removexattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_removexattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+removexattr[\s]+|([\s]+|[,])removexattr([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit removexattr  oval:ssg-test_32bit_ardm_removexattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_removexattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+removexattr[\s]+|([\s]+|[,])removexattr([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit removexattr  oval:ssg-test_64bit_ardm_removexattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_removexattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+removexattr[\s]+|([\s]+|[,])removexattr([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Record Events that Modify the System's Discretionary Access Controls - setxattrxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_setxattr medium

Record Events that Modify the System's Discretionary Access Controls - setxattr

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_setxattr
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_dac_modification_setxattr:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, 5.4.1.1, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000126, CCI-000130, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.5.5, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000064-GPOS-00033, SRG-OS-000458-GPOS-00203, SRG-OS-000458-VMM-001810, SRG-OS-000474-VMM-001940

Description
At a minimum, the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S setxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S setxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S setxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S setxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
Rationale
The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="setxattr"
	KEY="perm_mod"
	SYSCALL_GROUPING="fremovexattr lremovexattr removexattr fsetxattr lsetxattr setxattr"

	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_setxattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit setxattr tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_setxattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for setxattr for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - setxattr
        syscall_grouping:
          - fremovexattr
          - lremovexattr
          - removexattr
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of setxattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
      set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - setxattr
        syscall_grouping:
          - fremovexattr
          - lremovexattr
          - removexattr
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of setxattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_setxattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for setxattr for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - setxattr
        syscall_grouping:
          - fremovexattr
          - lremovexattr
          - removexattr
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of setxattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
      set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - setxattr
        syscall_grouping:
          - fremovexattr
          - lremovexattr
          - removexattr
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of setxattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=perm_mod
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_dac_modification_setxattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit setxattr  oval:ssg-test_32bit_ardm_setxattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_setxattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+setxattr[\s]+|([\s]+|[,])setxattr([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit setxattr  oval:ssg-test_64bit_ardm_setxattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_setxattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+setxattr[\s]+|([\s]+|[,])setxattr([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit setxattr  oval:ssg-test_32bit_ardm_setxattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_setxattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+setxattr[\s]+|([\s]+|[,])setxattr([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit setxattr  oval:ssg-test_64bit_ardm_setxattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_setxattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+setxattr[\s]+|([\s]+|[,])setxattr([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Record Any Attempts to Run chconxccdf_org.ssgproject.content_rule_audit_rules_execution_chcon medium

Record Any Attempts to Run chcon

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_execution_chcon
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_execution_chcon:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000130, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2, AU-2(d), AU-12(c), AC-6(9), CM-6(a), DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1, FAU_GEN.1.1.c, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000468-GPOS-00212, SRG-OS-000471-GPOS-00215, SRG-OS-000463-GPOS-00207, SRG-OS-000465-GPOS-00209, SRG-OS-000463-VMM-001850

Description
At a minimum, the audit system should collect any execution attempt of the chcon command for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/bin/chcon -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F path=/usr/bin/chcon -F auid>=1000 -F auid!=unset -F key=privileged
Rationale
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/bin/chcon"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_execution_chcon
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Perform remediation of Audit rules for /usr/bin/chcon
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/bin/chcon -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
      set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/chcon -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/chcon -F auid>=1000
          -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/bin/chcon -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|")
          }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/chcon -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/chcon -F auid>=1000
          -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_execution_chcon
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules chcon  oval:ssg-test_audit_rules_execution_chcon_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_execution_chcon_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/bin\/chcon[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl chcon  oval:ssg-test_audit_rules_execution_chcon_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_execution_chcon_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/bin\/chcon[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Record Any Attempts to Run restoreconxccdf_org.ssgproject.content_rule_audit_rules_execution_restorecon medium

Record Any Attempts to Run restorecon

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_execution_restorecon
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_execution_restorecon:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2, AU-2(d), AU-12(c), AC-6(9), CM-6(a), DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1, FAU_GEN.1.1.c, SRG-OS-000392-GPOS-00172, SRG-OS-000463-GPOS-00207, SRG-OS-000465-GPOS-00209, SRG-OS-000463-VMM-001850

Description
At a minimum, the audit system should collect any execution attempt of the restorecon command for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/sbin/restorecon -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F path=/usr/sbin/restorecon -F auid>=1000 -F auid!=unset -F key=privileged
Rationale
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/sbin/restorecon"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_execution_restorecon
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Perform remediation of Audit rules for /usr/sbin/restorecon
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/sbin/restorecon -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
      set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/sbin/restorecon -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/sbin/restorecon
          -F auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/sbin/restorecon -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|")
          }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/sbin/restorecon -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/sbin/restorecon
          -F auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_execution_restorecon
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules restorecon  oval:ssg-test_audit_rules_execution_restorecon_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_execution_restorecon_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/sbin\/restorecon[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl restorecon  oval:ssg-test_audit_rules_execution_restorecon_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_execution_restorecon_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/sbin\/restorecon[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Record Any Attempts to Run semanagexccdf_org.ssgproject.content_rule_audit_rules_execution_semanage medium

Record Any Attempts to Run semanage

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_execution_semanage
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_execution_semanage:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2, CIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3, AC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a), DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1, FAU_GEN.1.1.c, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000463-GPOS-00207, SRG-OS-000465-GPOS-00209, SRG-OS-000463-VMM-001850

Description
At a minimum, the audit system should collect any execution attempt of the semanage command for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/sbin/semanage -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F path=/usr/sbin/semanage -F auid>=1000 -F auid!=unset -F key=privileged
Rationale
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/sbin/semanage"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_execution_semanage
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Perform remediation of Audit rules for /usr/sbin/semanage
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/sbin/semanage -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
      set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/sbin/semanage -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/sbin/semanage
          -F auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/sbin/semanage -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|")
          }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/sbin/semanage -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/sbin/semanage
          -F auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_execution_semanage
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules semanage  oval:ssg-test_audit_rules_execution_semanage_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_execution_semanage_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/sbin\/semanage[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl semanage  oval:ssg-test_audit_rules_execution_semanage_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_execution_semanage_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/sbin\/semanage[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Record Any Attempts to Run setseboolxccdf_org.ssgproject.content_rule_audit_rules_execution_setsebool medium

Record Any Attempts to Run setsebool

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_execution_setsebool
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_execution_setsebool:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2, AU-2(d), AU-12(c), AC-6(9), CM-6(a), DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1, FAU_GEN.1.1.c, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000463-GPOS-00207, SRG-OS-000465-GPOS-00209, SRG-OS-000463-VMM-001850

Description
At a minimum, the audit system should collect any execution attempt of the setsebool command for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/sbin/setsebool -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F path=/usr/sbin/setsebool -F auid>=1000 -F auid!=unset -F key=privileged
Rationale
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/sbin/setsebool"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_execution_setsebool
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Perform remediation of Audit rules for /usr/sbin/setsebool
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/sbin/setsebool -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
      set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/sbin/setsebool -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/sbin/setsebool
          -F auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/sbin/setsebool -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|")
          }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/sbin/setsebool -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/sbin/setsebool
          -F auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_execution_setsebool
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules setsebool  oval:ssg-test_audit_rules_execution_setsebool_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_execution_setsebool_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/sbin\/setsebool[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl setsebool  oval:ssg-test_audit_rules_execution_setsebool_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_execution_setsebool_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/sbin\/setsebool[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Record Any Attempts to Run seunsharexccdf_org.ssgproject.content_rule_audit_rules_execution_seunshare medium

Record Any Attempts to Run seunshare

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_execution_seunshare
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_execution_seunshare:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-000172, AU-2(d), AU-12(c), AC-6(9), CM-6(a), FAU_GEN.1.1.c, SRG-OS-000463-VMM-001850

Description
At a minimum, the audit system should collect any execution attempt of the seunshare command for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/sbin/seunshare -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F path=/usr/sbin/seunshare -F auid>=1000 -F auid!=unset -F key=privileged
Rationale
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/sbin/seunshare"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_execution_seunshare
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Perform remediation of Audit rules for /usr/sbin/seunshare
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/sbin/seunshare -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
      set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/sbin/seunshare -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/sbin/seunshare
          -F auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/sbin/seunshare -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|")
          }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/sbin/seunshare -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/sbin/seunshare
          -F auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_execution_seunshare
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules seunshare  oval:ssg-test_audit_rules_execution_seunshare_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_execution_seunshare_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/sbin\/seunshare[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl seunshare  oval:ssg-test_audit_rules_execution_seunshare_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_execution_seunshare_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/sbin\/seunshare[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Ensure auditd Collects File Deletion Events by User - renamexccdf_org.ssgproject.content_rule_audit_rules_file_deletion_events_rename medium

Ensure auditd Collects File Deletion Events by User - rename

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_file_deletion_events_rename
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_file_deletion_events_rename:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000169, CCI-000172, CCI-000366, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.4, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.1.1, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.MA-2, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.2.7, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000466-GPOS-00210, SRG-OS-000467-GPOS-00211, SRG-OS-000468-GPOS-00212, SRG-OS-000466-VMM-001870, SRG-OS-000468-VMM-001890

Description
At a minimum, the audit system should collect file deletion events for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d, setting ARCH to either b32 or b64 as appropriate for your system:
-a always,exit -F arch=ARCH -S rename -F auid>=1000 -F auid!=unset -F key=delete
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file, setting ARCH to either b32 or b64 as appropriate for your system:
-a always,exit -F arch=ARCH -S rename -F auid>=1000 -F auid!=unset -F key=delete
Rationale
Auditing file deletions will create an audit trail for files that are removed from the system. The audit trail could aid in system troubleshooting, as well as, detecting malicious processes that attempt to delete log files to conceal their presence.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="rename"
	KEY="delete"
	SYSCALL_GROUPING="unlink unlinkat rename renameat rmdir"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.7
    - audit_rules_file_deletion_events_rename
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit rename tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.7
    - audit_rules_file_deletion_events_rename
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for rename for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - rename
        syscall_grouping:
          - unlink
          - unlinkat
          - rename
          - renameat
          - rmdir

    - name: Check existence of rename in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/delete.rules
      set_fact: audit_file="/etc/audit/rules.d/delete.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=delete
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - rename
        syscall_grouping:
          - unlink
          - unlinkat
          - rename
          - renameat
          - rmdir

    - name: Check existence of rename in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=delete
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.7
    - audit_rules_file_deletion_events_rename
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for rename for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - rename
        syscall_grouping:
          - unlink
          - unlinkat
          - rename
          - renameat
          - rmdir

    - name: Check existence of rename in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/delete.rules
      set_fact: audit_file="/etc/audit/rules.d/delete.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=delete
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - rename
        syscall_grouping:
          - unlink
          - unlinkat
          - rename
          - renameat
          - rmdir

    - name: Check existence of rename in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=delete
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.7
    - audit_rules_file_deletion_events_rename
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit rename  oval:ssg-test_32bit_ardm_rename_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_rename_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+rename[\s]+|([\s]+|[,])rename([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit rename  oval:ssg-test_64bit_ardm_rename_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_rename_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+rename[\s]+|([\s]+|[,])rename([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit rename  oval:ssg-test_32bit_ardm_rename_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_rename_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+rename[\s]+|([\s]+|[,])rename([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit rename  oval:ssg-test_64bit_ardm_rename_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_rename_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+rename[\s]+|([\s]+|[,])rename([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Ensure auditd Collects File Deletion Events by User - renameatxccdf_org.ssgproject.content_rule_audit_rules_file_deletion_events_renameat medium

Ensure auditd Collects File Deletion Events by User - renameat

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_file_deletion_events_renameat
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_file_deletion_events_renameat:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000169, CCI-000172, CCI-000366, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.4, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.1.1, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.MA-2, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.2.7, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000466-GPOS-00210, SRG-OS-000467-GPOS-00211, SRG-OS-000468-GPOS-00212, SRG-OS-000466-VMM-001870, SRG-OS-000468-VMM-001890

Description
At a minimum, the audit system should collect file deletion events for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d, setting ARCH to either b32 or b64 as appropriate for your system:
-a always,exit -F arch=ARCH -S renameat -F auid>=1000 -F auid!=unset -F key=delete
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file, setting ARCH to either b32 or b64 as appropriate for your system:
-a always,exit -F arch=ARCH -S renameat -F auid>=1000 -F auid!=unset -F key=delete
Rationale
Auditing file deletions will create an audit trail for files that are removed from the system. The audit trail could aid in system troubleshooting, as well as, detecting malicious processes that attempt to delete log files to conceal their presence.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="renameat"
	KEY="delete"
	SYSCALL_GROUPING="unlink unlinkat rename renameat rmdir"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.7
    - audit_rules_file_deletion_events_renameat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit renameat tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.7
    - audit_rules_file_deletion_events_renameat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for renameat for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - renameat
        syscall_grouping:
          - unlink
          - unlinkat
          - rename
          - renameat
          - rmdir

    - name: Check existence of renameat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/delete.rules
      set_fact: audit_file="/etc/audit/rules.d/delete.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=delete
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - renameat
        syscall_grouping:
          - unlink
          - unlinkat
          - rename
          - renameat
          - rmdir

    - name: Check existence of renameat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=delete
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.7
    - audit_rules_file_deletion_events_renameat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for renameat for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - renameat
        syscall_grouping:
          - unlink
          - unlinkat
          - rename
          - renameat
          - rmdir

    - name: Check existence of renameat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/delete.rules
      set_fact: audit_file="/etc/audit/rules.d/delete.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=delete
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - renameat
        syscall_grouping:
          - unlink
          - unlinkat
          - rename
          - renameat
          - rmdir

    - name: Check existence of renameat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=delete
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.7
    - audit_rules_file_deletion_events_renameat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit renameat  oval:ssg-test_32bit_ardm_renameat_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_renameat_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+renameat[\s]+|([\s]+|[,])renameat([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit renameat  oval:ssg-test_64bit_ardm_renameat_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_renameat_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+renameat[\s]+|([\s]+|[,])renameat([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit renameat  oval:ssg-test_32bit_ardm_renameat_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_renameat_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+renameat[\s]+|([\s]+|[,])renameat([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit renameat  oval:ssg-test_64bit_ardm_renameat_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_renameat_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+renameat[\s]+|([\s]+|[,])renameat([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Ensure auditd Collects File Deletion Events by User - rmdirxccdf_org.ssgproject.content_rule_audit_rules_file_deletion_events_rmdir medium

Ensure auditd Collects File Deletion Events by User - rmdir

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_file_deletion_events_rmdir
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_file_deletion_events_rmdir:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000169, CCI-000172, CCI-000366, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.4, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.1.1, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.MA-2, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.2.7, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000466-GPOS-00210, SRG-OS-000467-GPOS-00211, SRG-OS-000468-GPOS-00212, SRG-OS-000466-VMM-001870, SRG-OS-000468-VMM-001890

Description
At a minimum, the audit system should collect file deletion events for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d, setting ARCH to either b32 or b64 as appropriate for your system:
-a always,exit -F arch=ARCH -S rmdir -F auid>=1000 -F auid!=unset -F key=delete
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file, setting ARCH to either b32 or b64 as appropriate for your system:
-a always,exit -F arch=ARCH -S rmdir -F auid>=1000 -F auid!=unset -F key=delete
Rationale
Auditing file deletions will create an audit trail for files that are removed from the system. The audit trail could aid in system troubleshooting, as well as, detecting malicious processes that attempt to delete log files to conceal their presence.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="rmdir"
	KEY="delete"
	SYSCALL_GROUPING="unlink unlinkat rename renameat rmdir"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.7
    - audit_rules_file_deletion_events_rmdir
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit rmdir tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.7
    - audit_rules_file_deletion_events_rmdir
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for rmdir for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - rmdir
        syscall_grouping:
          - unlink
          - unlinkat
          - rename
          - renameat
          - rmdir

    - name: Check existence of rmdir in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/delete.rules
      set_fact: audit_file="/etc/audit/rules.d/delete.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=delete
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - rmdir
        syscall_grouping:
          - unlink
          - unlinkat
          - rename
          - renameat
          - rmdir

    - name: Check existence of rmdir in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=delete
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.7
    - audit_rules_file_deletion_events_rmdir
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for rmdir for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - rmdir
        syscall_grouping:
          - unlink
          - unlinkat
          - rename
          - renameat
          - rmdir

    - name: Check existence of rmdir in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/delete.rules
      set_fact: audit_file="/etc/audit/rules.d/delete.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=delete
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - rmdir
        syscall_grouping:
          - unlink
          - unlinkat
          - rename
          - renameat
          - rmdir

    - name: Check existence of rmdir in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=delete
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.7
    - audit_rules_file_deletion_events_rmdir
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit rmdir  oval:ssg-test_32bit_ardm_rmdir_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_rmdir_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+rmdir[\s]+|([\s]+|[,])rmdir([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit rmdir  oval:ssg-test_64bit_ardm_rmdir_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_rmdir_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+rmdir[\s]+|([\s]+|[,])rmdir([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit rmdir  oval:ssg-test_32bit_ardm_rmdir_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_rmdir_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+rmdir[\s]+|([\s]+|[,])rmdir([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit rmdir  oval:ssg-test_64bit_ardm_rmdir_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_rmdir_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+rmdir[\s]+|([\s]+|[,])rmdir([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Ensure auditd Collects File Deletion Events by User - unlinkatxccdf_org.ssgproject.content_rule_audit_rules_file_deletion_events_unlinkat medium

Ensure auditd Collects File Deletion Events by User - unlinkat

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_file_deletion_events_unlinkat
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_file_deletion_events_unlinkat:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000169, CCI-000172, CCI-000366, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.4, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.1.1, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.MA-2, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.2.7, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000466-GPOS-00210, SRG-OS-000467-GPOS-00211, SRG-OS-000468-GPOS-00212, SRG-OS-000466-VMM-001870, SRG-OS-000468-VMM-001890

Description
At a minimum, the audit system should collect file deletion events for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d, setting ARCH to either b32 or b64 as appropriate for your system:
-a always,exit -F arch=ARCH -S unlinkat -F auid>=1000 -F auid!=unset -F key=delete
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file, setting ARCH to either b32 or b64 as appropriate for your system:
-a always,exit -F arch=ARCH -S unlinkat -F auid>=1000 -F auid!=unset -F key=delete
Rationale
Auditing file deletions will create an audit trail for files that are removed from the system. The audit trail could aid in system troubleshooting, as well as, detecting malicious processes that attempt to delete log files to conceal their presence.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="unlinkat"
	KEY="delete"
	SYSCALL_GROUPING="unlink unlinkat rename renameat rmdir"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.7
    - audit_rules_file_deletion_events_unlinkat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit unlinkat tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.7
    - audit_rules_file_deletion_events_unlinkat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for unlinkat for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - unlinkat
        syscall_grouping:
          - unlink
          - unlinkat
          - rename
          - renameat
          - rmdir

    - name: Check existence of unlinkat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/delete.rules
      set_fact: audit_file="/etc/audit/rules.d/delete.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=delete
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - unlinkat
        syscall_grouping:
          - unlink
          - unlinkat
          - rename
          - renameat
          - rmdir

    - name: Check existence of unlinkat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=delete
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.7
    - audit_rules_file_deletion_events_unlinkat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for unlinkat for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - unlinkat
        syscall_grouping:
          - unlink
          - unlinkat
          - rename
          - renameat
          - rmdir

    - name: Check existence of unlinkat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/delete.rules
      set_fact: audit_file="/etc/audit/rules.d/delete.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=delete
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - unlinkat
        syscall_grouping:
          - unlink
          - unlinkat
          - rename
          - renameat
          - rmdir

    - name: Check existence of unlinkat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
          |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
          -F auid!=unset -F key=delete
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.7
    - audit_rules_file_deletion_events_unlinkat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit unlinkat  oval:ssg-test_32bit_ardm_unlinkat_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_unlinkat_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+unlinkat[\s]+|([\s]+|[,])unlinkat([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit unlinkat  oval:ssg-test_64bit_ardm_unlinkat_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_unlinkat_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+unlinkat[\s]+|([\s]+|[,])unlinkat([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit unlinkat  oval:ssg-test_32bit_ardm_unlinkat_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_unlinkat_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+unlinkat[\s]+|([\s]+|[,])unlinkat([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit unlinkat  oval:ssg-test_64bit_ardm_unlinkat_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_unlinkat_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+unlinkat[\s]+|([\s]+|[,])unlinkat([\s]+|[,])))(?:.*-F\s+auid>=1000[\s]+)(?:.*-F\s+auid!=(?:4294967295|unset)[\s]+).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Record Unsuccessul Permission Changes to Files - chmodxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_chmod medium

Record Unsuccessul Permission Changes to Files - chmod

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_chmod
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_unsuccessful_file_modification_chmod:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-000172, AU-2(d), AU-12(c), CM-6(a), SRG-OS-000458-VMM-001810, SRG-OS-000461-VMM-001830

Description
The audit system should collect unsuccessful file permission change attempts for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d. If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file.
-a always,exit -F arch=b32 -S chmod -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
-a always,exit -F arch=b32 -S chmod -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S chmod -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
-a always,exit -F arch=b64 -S chmod -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
Rationale
Unsuccessful attempts to change permissions of files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the audit rule checks a system call independently of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S chmod,fchmod,fchmodat,setxattr,lsetxattr,fsetxattr -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL="chmod"
KEY="access"
SYSCALL_GROUPING="chmod fchmod fchmodat fsetxattr lsetxattr setxattr"

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EACCES"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EPERM"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_chmod
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit chmod tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_chmod
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for chmod EACCES for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - chmod
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of chmod in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - chmod
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of chmod in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_chmod
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for chmod EACCES for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - chmod
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of chmod in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - chmod
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of chmod in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_chmod
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for chmod EPERM for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - chmod
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of chmod in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - chmod
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of chmod in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_chmod
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for chmod EPERM for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - chmod
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of chmod in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - chmod
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of chmod in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_chmod
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_chmod_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_chmod_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+chmod[\s]+|([\s]+|[,])chmod([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+chmod[\s]+|([\s]+|[,])chmod([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_chmod_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_chmod_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+chmod[\s]+|([\s]+|[,])chmod([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+chmod[\s]+|([\s]+|[,])chmod([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_chmod_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_chmod_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+chmod[\s]+|([\s]+|[,])chmod([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+chmod[\s]+|([\s]+|[,])chmod([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_chmod_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_chmod_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+chmod[\s]+|([\s]+|[,])chmod([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+chmod[\s]+|([\s]+|[,])chmod([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_chmod_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_chmod_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+chmod[\s]+|([\s]+|[,])chmod([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+chmod[\s]+|([\s]+|[,])chmod([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
/etc/audit/audit.rules1

audit auditctl 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_chmod_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_chmod_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+chmod[\s]+|([\s]+|[,])chmod([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+chmod[\s]+|([\s]+|[,])chmod([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_chmod_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_chmod_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+chmod[\s]+|([\s]+|[,])chmod([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+chmod[\s]+|([\s]+|[,])chmod([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
/etc/audit/audit.rules1

audit auditctl 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_chmod_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_chmod_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+chmod[\s]+|([\s]+|[,])chmod([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+chmod[\s]+|([\s]+|[,])chmod([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
/etc/audit/audit.rules1
Record Unsuccessul Ownership Changes to Files - chownxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_chown medium

Record Unsuccessul Ownership Changes to Files - chown

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_chown
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_unsuccessful_file_modification_chown:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-000172, AU-2(d), AU-12(c), CM-6(a), SRG-OS-000458-VMM-001810, SRG-OS-000461-VMM-001830

Description
The audit system should collect unsuccessful file ownership change attempts for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d. If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file.
-a always,exit -F arch=b32 -S chown -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
-a always,exit -F arch=b32 -S chown -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S chown -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
-a always,exit -F arch=b64 -S chown -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
Rationale
Unsuccessful attempts to change ownership of files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the audit rule checks a system call independently of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S lchown,fchown,chown,fchownat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL="chown"
KEY="access"
SYSCALL_GROUPING="chown fchown fchownat lchown"

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EACCES"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EPERM"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_chown
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit chown tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_chown
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for chown EACCES for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - chown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of chown in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - chown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of chown in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_chown
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for chown EACCES for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - chown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of chown in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - chown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of chown in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_chown
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for chown EPERM for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - chown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of chown in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - chown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of chown in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_chown
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for chown EPERM for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - chown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of chown in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - chown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of chown in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_chown
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_chown_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_chown_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+chown[\s]+|([\s]+|[,])chown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+chown[\s]+|([\s]+|[,])chown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_chown_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_chown_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+chown[\s]+|([\s]+|[,])chown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+chown[\s]+|([\s]+|[,])chown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_chown_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_chown_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+chown[\s]+|([\s]+|[,])chown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+chown[\s]+|([\s]+|[,])chown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_chown_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_chown_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+chown[\s]+|([\s]+|[,])chown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+chown[\s]+|([\s]+|[,])chown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_chown_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_chown_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+chown[\s]+|([\s]+|[,])chown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+chown[\s]+|([\s]+|[,])chown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
/etc/audit/audit.rules1

audit auditctl 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_chown_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_chown_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+chown[\s]+|([\s]+|[,])chown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+chown[\s]+|([\s]+|[,])chown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_chown_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_chown_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+chown[\s]+|([\s]+|[,])chown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+chown[\s]+|([\s]+|[,])chown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
/etc/audit/audit.rules1

audit auditctl 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_chown_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_chown_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+chown[\s]+|([\s]+|[,])chown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+chown[\s]+|([\s]+|[,])chown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
/etc/audit/audit.rules1
Record Unsuccessful Access Attempts to Files - creatxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_creat medium

Record Unsuccessful Access Attempts to Files - creat

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_creat
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_unsuccessful_file_modification_creat:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000130, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.2.4, Req-10.2.1, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000064-GPOS-00033, SRG-OS-000458-GPOS-00203, SRG-OS-000461-GPOS-00205, SRG-OS-000458-VMM-001810, SRG-OS-000461-VMM-001830

Description
At a minimum, the audit system should collect unauthorized file accesses for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S creat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S creat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S creat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S creat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S creat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S creat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S creat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S creat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
Rationale
Unsuccessful attempts to access files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL="creat"
KEY="access"
SYSCALL_GROUPING="creat ftruncate truncate open openat open_by_handle_at"

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EACCES"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EPERM"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_creat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit creat tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_creat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for creat EACCES for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - creat
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of creat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - creat
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of creat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_creat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for creat EACCES for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - creat
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of creat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - creat
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of creat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_creat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for creat EPERM for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - creat
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of creat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - creat
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of creat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_creat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for creat EPERM for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - creat
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of creat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - creat
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of creat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_creat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_creat_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_creat_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+creat[\s]+|([\s]+|[,])creat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+creat[\s]+|([\s]+|[,])creat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_creat_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_creat_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+creat[\s]+|([\s]+|[,])creat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+creat[\s]+|([\s]+|[,])creat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_creat_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_creat_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+creat[\s]+|([\s]+|[,])creat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+creat[\s]+|([\s]+|[,])creat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_creat_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_creat_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+creat[\s]+|([\s]+|[,])creat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+creat[\s]+|([\s]+|[,])creat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_creat_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_creat_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+creat[\s]+|([\s]+|[,])creat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+creat[\s]+|([\s]+|[,])creat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
/etc/audit/audit.rules1

audit auditctl 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_creat_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_creat_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+creat[\s]+|([\s]+|[,])creat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+creat[\s]+|([\s]+|[,])creat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_creat_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_creat_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+creat[\s]+|([\s]+|[,])creat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+creat[\s]+|([\s]+|[,])creat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
/etc/audit/audit.rules1

audit auditctl 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_creat_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_creat_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+creat[\s]+|([\s]+|[,])creat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+creat[\s]+|([\s]+|[,])creat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
/etc/audit/audit.rules1
Record Unsuccessul Permission Changes to Files - fchmodxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_fchmod medium

Record Unsuccessul Permission Changes to Files - fchmod

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_fchmod
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_unsuccessful_file_modification_fchmod:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-000172, AU-2(d), AU-12(c), CM-6(a), SRG-OS-000458-VMM-001810, SRG-OS-000461-VMM-001830

Description
The audit system should collect unsuccessful file permission change attempts for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d. If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file.
-a always,exit -F arch=b32 -S fchmod -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
-a always,exit -F arch=b32 -S fchmod -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S fchmod -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
-a always,exit -F arch=b64 -S fchmod -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
Rationale
Unsuccessful attempts to change permissions of files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the audit rule checks a system call independently of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S chmod,fchmod,fchmodat,setxattr,lsetxattr,fsetxattr -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL="fchmod"
KEY="access"
SYSCALL_GROUPING="chmod fchmod fchmodat fsetxattr lsetxattr setxattr"

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EACCES"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EPERM"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fchmod
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit fchmod tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fchmod
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fchmod EACCES for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchmod
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of fchmod in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchmod
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of fchmod in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fchmod
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fchmod EACCES for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchmod
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of fchmod in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchmod
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of fchmod in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fchmod
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fchmod EPERM for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchmod
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of fchmod in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchmod
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of fchmod in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fchmod
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fchmod EPERM for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchmod
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of fchmod in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchmod
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of fchmod in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fchmod
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_fchmod_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_fchmod_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchmod[\s]+|([\s]+|[,])fchmod([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchmod[\s]+|([\s]+|[,])fchmod([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_fchmod_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_fchmod_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchmod[\s]+|([\s]+|[,])fchmod([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchmod[\s]+|([\s]+|[,])fchmod([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_fchmod_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_fchmod_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchmod[\s]+|([\s]+|[,])fchmod([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchmod[\s]+|([\s]+|[,])fchmod([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_fchmod_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_fchmod_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchmod[\s]+|([\s]+|[,])fchmod([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchmod[\s]+|([\s]+|[,])fchmod([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_fchmod_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_fchmod_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchmod[\s]+|([\s]+|[,])fchmod([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchmod[\s]+|([\s]+|[,])fchmod([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_fchmod_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_fchmod_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchmod[\s]+|([\s]+|[,])fchmod([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchmod[\s]+|([\s]+|[,])fchmod([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_fchmod_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_fchmod_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchmod[\s]+|([\s]+|[,])fchmod([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchmod[\s]+|([\s]+|[,])fchmod([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_fchmod_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_fchmod_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchmod[\s]+|([\s]+|[,])fchmod([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchmod[\s]+|([\s]+|[,])fchmod([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1
Record Unsuccessul Permission Changes to Files - fchmodatxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_fchmodat medium

Record Unsuccessul Permission Changes to Files - fchmodat

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_fchmodat
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_unsuccessful_file_modification_fchmodat:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-000172, AU-2(d), AU-12(c), CM-6(a), SRG-OS-000458-VMM-001810, SRG-OS-000461-VMM-001830

Description
The audit system should collect unsuccessful file permission change attempts for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d. If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file.
-a always,exit -F arch=b32 -S fchmodat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
-a always,exit -F arch=b32 -S fchmodat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S fchmodat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
-a always,exit -F arch=b64 -S fchmodat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
Rationale
Unsuccessful attempts to change permissions of files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the audit rule checks a system call independently of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S chmod,fchmod,fchmodat,setxattr,lsetxattr,fsetxattr -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL="fchmodat"
KEY="access"
SYSCALL_GROUPING="chmod fchmod fchmodat fsetxattr lsetxattr setxattr"

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EACCES"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EPERM"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fchmodat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit fchmodat tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fchmodat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fchmodat EACCES for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchmodat
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of fchmodat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchmodat
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of fchmodat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fchmodat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fchmodat EACCES for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchmodat
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of fchmodat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchmodat
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of fchmodat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fchmodat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fchmodat EPERM for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchmodat
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of fchmodat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchmodat
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of fchmodat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fchmodat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fchmodat EPERM for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchmodat
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of fchmodat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchmodat
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of fchmodat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fchmodat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_fchmodat_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_fchmodat_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchmodat[\s]+|([\s]+|[,])fchmodat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchmodat[\s]+|([\s]+|[,])fchmodat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_fchmodat_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_fchmodat_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchmodat[\s]+|([\s]+|[,])fchmodat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchmodat[\s]+|([\s]+|[,])fchmodat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_fchmodat_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_fchmodat_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchmodat[\s]+|([\s]+|[,])fchmodat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchmodat[\s]+|([\s]+|[,])fchmodat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_fchmodat_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_fchmodat_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchmodat[\s]+|([\s]+|[,])fchmodat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchmodat[\s]+|([\s]+|[,])fchmodat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_fchmodat_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_fchmodat_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchmodat[\s]+|([\s]+|[,])fchmodat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchmodat[\s]+|([\s]+|[,])fchmodat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_fchmodat_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_fchmodat_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchmodat[\s]+|([\s]+|[,])fchmodat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchmodat[\s]+|([\s]+|[,])fchmodat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_fchmodat_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_fchmodat_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchmodat[\s]+|([\s]+|[,])fchmodat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchmodat[\s]+|([\s]+|[,])fchmodat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_fchmodat_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_fchmodat_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchmodat[\s]+|([\s]+|[,])fchmodat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchmodat[\s]+|([\s]+|[,])fchmodat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1
Record Unsuccessul Ownership Changes to Files - fchownxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_fchown medium

Record Unsuccessul Ownership Changes to Files - fchown

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_fchown
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_unsuccessful_file_modification_fchown:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-000172, AU-2(d), AU-12(c), CM-6(a), SRG-OS-000458-VMM-001810, SRG-OS-000461-VMM-001830

Description
The audit system should collect unsuccessful file ownership change attempts for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d. If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file.
-a always,exit -F arch=b32 -S fchown -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
-a always,exit -F arch=b32 -S fchown -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S fchown -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
-a always,exit -F arch=b64 -S fchown -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
Rationale
Unsuccessful attempts to change ownership of files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the audit rule checks a system call independently of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S lchown,fchown,chown,fchownat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL="fchown"
KEY="access"
SYSCALL_GROUPING="chown fchown fchownat lchown"

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EACCES"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EPERM"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fchown
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit fchown tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fchown
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fchown EACCES for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of fchown in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of fchown in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fchown
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fchown EACCES for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of fchown in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of fchown in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fchown
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fchown EPERM for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of fchown in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of fchown in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fchown
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fchown EPERM for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of fchown in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of fchown in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fchown
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_fchown_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_fchown_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchown[\s]+|([\s]+|[,])fchown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchown[\s]+|([\s]+|[,])fchown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_fchown_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_fchown_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchown[\s]+|([\s]+|[,])fchown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchown[\s]+|([\s]+|[,])fchown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_fchown_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_fchown_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchown[\s]+|([\s]+|[,])fchown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchown[\s]+|([\s]+|[,])fchown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_fchown_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_fchown_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchown[\s]+|([\s]+|[,])fchown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchown[\s]+|([\s]+|[,])fchown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_fchown_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_fchown_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchown[\s]+|([\s]+|[,])fchown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchown[\s]+|([\s]+|[,])fchown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_fchown_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_fchown_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchown[\s]+|([\s]+|[,])fchown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchown[\s]+|([\s]+|[,])fchown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_fchown_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_fchown_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchown[\s]+|([\s]+|[,])fchown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchown[\s]+|([\s]+|[,])fchown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_fchown_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_fchown_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchown[\s]+|([\s]+|[,])fchown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchown[\s]+|([\s]+|[,])fchown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1
Record Unsuccessul Ownership Changes to Files - fchownatxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_fchownat medium

Record Unsuccessul Ownership Changes to Files - fchownat

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_fchownat
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_unsuccessful_file_modification_fchownat:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-000172, AU-2(d), AU-12(c), CM-6(a), SRG-OS-000458-VMM-001810, SRG-OS-000461-VMM-001830

Description
The audit system should collect unsuccessful file ownership change attempts for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d. If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file.
-a always,exit -F arch=b32 -S fchownat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
-a always,exit -F arch=b32 -S fchownat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S fchownat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
-a always,exit -F arch=b64 -S fchownat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
Rationale
Unsuccessful attempts to change ownership of files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the audit rule checks a system call independently of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S lchown,fchown,chown,fchownat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL="fchownat"
KEY="access"
SYSCALL_GROUPING="chown fchown fchownat lchown"

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EACCES"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EPERM"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fchownat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit fchownat tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fchownat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fchownat EACCES for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchownat
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of fchownat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchownat
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of fchownat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fchownat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fchownat EACCES for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchownat
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of fchownat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchownat
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of fchownat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fchownat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fchownat EPERM for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchownat
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of fchownat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchownat
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of fchownat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fchownat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fchownat EPERM for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchownat
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of fchownat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fchownat
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of fchownat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fchownat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_fchownat_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_fchownat_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchownat[\s]+|([\s]+|[,])fchownat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchownat[\s]+|([\s]+|[,])fchownat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_fchownat_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_fchownat_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchownat[\s]+|([\s]+|[,])fchownat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchownat[\s]+|([\s]+|[,])fchownat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_fchownat_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_fchownat_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchownat[\s]+|([\s]+|[,])fchownat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchownat[\s]+|([\s]+|[,])fchownat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_fchownat_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_fchownat_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchownat[\s]+|([\s]+|[,])fchownat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchownat[\s]+|([\s]+|[,])fchownat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_fchownat_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_fchownat_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchownat[\s]+|([\s]+|[,])fchownat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchownat[\s]+|([\s]+|[,])fchownat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_fchownat_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_fchownat_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchownat[\s]+|([\s]+|[,])fchownat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fchownat[\s]+|([\s]+|[,])fchownat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_fchownat_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_fchownat_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchownat[\s]+|([\s]+|[,])fchownat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchownat[\s]+|([\s]+|[,])fchownat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_fchownat_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_fchownat_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchownat[\s]+|([\s]+|[,])fchownat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fchownat[\s]+|([\s]+|[,])fchownat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1
Record Unsuccessul Permission Changes to Files - fremovexattrxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_fremovexattr medium

Record Unsuccessul Permission Changes to Files - fremovexattr

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_fremovexattr
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_unsuccessful_file_modification_fremovexattr:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-000172, AU-2(d), AU-12(c), CM-6(a), SRG-OS-000458-VMM-001810, SRG-OS-000461-VMM-001830

Description
The audit system should collect unsuccessful file permission change attempts for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d. If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file.
-a always,exit -F arch=b32 -S fremovexattr -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
-a always,exit -F arch=b32 -S fremovexattr -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S fremovexattr -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
-a always,exit -F arch=b64 -S fremovexattr -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
Rationale
Unsuccessful attempts to change permissions of files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the audit rule checks a system call independently of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S chmod,fchmod,fchmodat,setxattr,lsetxattr,fsetxattr -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL="fremovexattr"
KEY="access"
SYSCALL_GROUPING=""

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EACCES"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EPERM"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fremovexattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit fremovexattr tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fremovexattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fremovexattr EACCES for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fremovexattr
        syscall_grouping: []

    - name: Check existence of fremovexattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fremovexattr
        syscall_grouping: []

    - name: Check existence of fremovexattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fremovexattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fremovexattr EACCES for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fremovexattr
        syscall_grouping: []

    - name: Check existence of fremovexattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fremovexattr
        syscall_grouping: []

    - name: Check existence of fremovexattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fremovexattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fremovexattr EPERM for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fremovexattr
        syscall_grouping: []

    - name: Check existence of fremovexattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fremovexattr
        syscall_grouping: []

    - name: Check existence of fremovexattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fremovexattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fremovexattr EPERM for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fremovexattr
        syscall_grouping: []

    - name: Check existence of fremovexattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fremovexattr
        syscall_grouping: []

    - name: Check existence of fremovexattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fremovexattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_fremovexattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_fremovexattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fremovexattr[\s]+|([\s]+|[,])fremovexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fremovexattr[\s]+|([\s]+|[,])fremovexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_fremovexattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_fremovexattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fremovexattr[\s]+|([\s]+|[,])fremovexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fremovexattr[\s]+|([\s]+|[,])fremovexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_fremovexattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_fremovexattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fremovexattr[\s]+|([\s]+|[,])fremovexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fremovexattr[\s]+|([\s]+|[,])fremovexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_fremovexattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_fremovexattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fremovexattr[\s]+|([\s]+|[,])fremovexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fremovexattr[\s]+|([\s]+|[,])fremovexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_fremovexattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_fremovexattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fremovexattr[\s]+|([\s]+|[,])fremovexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fremovexattr[\s]+|([\s]+|[,])fremovexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_fremovexattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_fremovexattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fremovexattr[\s]+|([\s]+|[,])fremovexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fremovexattr[\s]+|([\s]+|[,])fremovexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_fremovexattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_fremovexattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fremovexattr[\s]+|([\s]+|[,])fremovexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fremovexattr[\s]+|([\s]+|[,])fremovexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_fremovexattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_fremovexattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fremovexattr[\s]+|([\s]+|[,])fremovexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fremovexattr[\s]+|([\s]+|[,])fremovexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1
Record Unsuccessul Permission Changes to Files - fsetxattrxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_fsetxattr medium

Record Unsuccessul Permission Changes to Files - fsetxattr

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_fsetxattr
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_unsuccessful_file_modification_fsetxattr:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-000172, AU-2(d), AU-12(c), CM-6(a), SRG-OS-000458-VMM-001810, SRG-OS-000461-VMM-001830

Description
The audit system should collect unsuccessful file permission change attempts for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d. If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file.
-a always,exit -F arch=b32 -S fsetxattr -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
-a always,exit -F arch=b32 -S fsetxattr -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S fsetxattr -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
-a always,exit -F arch=b64 -S fsetxattr -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
Rationale
Unsuccessful attempts to change permissions of files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the audit rule checks a system call independently of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S chmod,fchmod,fchmodat,setxattr,lsetxattr,fsetxattr -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL="fsetxattr"
KEY="access"
SYSCALL_GROUPING="chmod fchmod fchmodat fsetxattr lsetxattr setxattr"

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EACCES"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EPERM"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fsetxattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit fsetxattr tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fsetxattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fsetxattr EACCES for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fsetxattr
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of fsetxattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fsetxattr
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of fsetxattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fsetxattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fsetxattr EACCES for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fsetxattr
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of fsetxattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fsetxattr
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of fsetxattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fsetxattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fsetxattr EPERM for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fsetxattr
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of fsetxattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fsetxattr
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of fsetxattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fsetxattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for fsetxattr EPERM for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fsetxattr
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of fsetxattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - fsetxattr
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of fsetxattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_fsetxattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_fsetxattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_fsetxattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fsetxattr[\s]+|([\s]+|[,])fsetxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fsetxattr[\s]+|([\s]+|[,])fsetxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_fsetxattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_fsetxattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fsetxattr[\s]+|([\s]+|[,])fsetxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fsetxattr[\s]+|([\s]+|[,])fsetxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_fsetxattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_fsetxattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fsetxattr[\s]+|([\s]+|[,])fsetxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fsetxattr[\s]+|([\s]+|[,])fsetxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_fsetxattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_fsetxattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fsetxattr[\s]+|([\s]+|[,])fsetxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fsetxattr[\s]+|([\s]+|[,])fsetxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_fsetxattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_fsetxattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fsetxattr[\s]+|([\s]+|[,])fsetxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fsetxattr[\s]+|([\s]+|[,])fsetxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_fsetxattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_fsetxattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fsetxattr[\s]+|([\s]+|[,])fsetxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+fsetxattr[\s]+|([\s]+|[,])fsetxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_fsetxattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_fsetxattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fsetxattr[\s]+|([\s]+|[,])fsetxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fsetxattr[\s]+|([\s]+|[,])fsetxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_fsetxattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_fsetxattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fsetxattr[\s]+|([\s]+|[,])fsetxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+fsetxattr[\s]+|([\s]+|[,])fsetxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1
Record Unsuccessful Access Attempts to Files - ftruncatexccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_ftruncate medium

Record Unsuccessful Access Attempts to Files - ftruncate

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_ftruncate
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_unsuccessful_file_modification_ftruncate:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000130, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.2.4, Req-10.2.1, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000064-GPOS-00033, SRG-OS-000458-GPOS-00203, SRG-OS-000461-GPOS-00205, SRG-OS-000458-VMM-001810, SRG-OS-000461-VMM-001830

Description
At a minimum, the audit system should collect unauthorized file accesses for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S ftruncate -F exiu=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
Rationale
Unsuccessful attempts to access files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL="ftruncate"
KEY="access"
SYSCALL_GROUPING="creat ftruncate truncate open openat open_by_handle_at"

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EACCES"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EPERM"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_ftruncate
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit ftruncate tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_ftruncate
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for ftruncate EACCES for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - ftruncate
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of ftruncate in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - ftruncate
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of ftruncate in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_ftruncate
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for ftruncate EACCES for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - ftruncate
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of ftruncate in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - ftruncate
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of ftruncate in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_ftruncate
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for ftruncate EPERM for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - ftruncate
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of ftruncate in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - ftruncate
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of ftruncate in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_ftruncate
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for ftruncate EPERM for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - ftruncate
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of ftruncate in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - ftruncate
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of ftruncate in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_ftruncate
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_ftruncate_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_ftruncate_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+ftruncate[\s]+|([\s]+|[,])ftruncate([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+ftruncate[\s]+|([\s]+|[,])ftruncate([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_ftruncate_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_ftruncate_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+ftruncate[\s]+|([\s]+|[,])ftruncate([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+ftruncate[\s]+|([\s]+|[,])ftruncate([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_ftruncate_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_ftruncate_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+ftruncate[\s]+|([\s]+|[,])ftruncate([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+ftruncate[\s]+|([\s]+|[,])ftruncate([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_ftruncate_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_ftruncate_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+ftruncate[\s]+|([\s]+|[,])ftruncate([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+ftruncate[\s]+|([\s]+|[,])ftruncate([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_ftruncate_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_ftruncate_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+ftruncate[\s]+|([\s]+|[,])ftruncate([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+ftruncate[\s]+|([\s]+|[,])ftruncate([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_ftruncate_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_ftruncate_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+ftruncate[\s]+|([\s]+|[,])ftruncate([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+ftruncate[\s]+|([\s]+|[,])ftruncate([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_ftruncate_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_ftruncate_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+ftruncate[\s]+|([\s]+|[,])ftruncate([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+ftruncate[\s]+|([\s]+|[,])ftruncate([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_ftruncate_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_ftruncate_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+ftruncate[\s]+|([\s]+|[,])ftruncate([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+ftruncate[\s]+|([\s]+|[,])ftruncate([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1
Record Unsuccessul Ownership Changes to Files - lchownxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_lchown medium

Record Unsuccessul Ownership Changes to Files - lchown

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_lchown
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_unsuccessful_file_modification_lchown:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-000172, AU-2(d), AU-12(c), CM-6(a), SRG-OS-000458-VMM-001810, SRG-OS-000461-VMM-001830

Description
The audit system should collect unsuccessful file ownership change attempts for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d. If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file.
-a always,exit -F arch=b32 -S lchown -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
-a always,exit -F arch=b32 -S lchown -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S lchown -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
-a always,exit -F arch=b64 -S lchown -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
Rationale
Unsuccessful attempts to change ownership of files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the audit rule checks a system call independently of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S lchown,fchown,chown,fchownat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL="lchown"
KEY="access"
SYSCALL_GROUPING="chown fchown fchownat lchown"

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EACCES"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EPERM"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_lchown
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit lchown tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_lchown
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for lchown EACCES for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lchown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of lchown in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lchown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of lchown in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_lchown
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for lchown EACCES for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lchown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of lchown in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lchown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of lchown in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_lchown
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for lchown EPERM for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lchown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of lchown in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lchown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of lchown in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_lchown
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for lchown EPERM for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lchown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of lchown in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lchown
        syscall_grouping:
          - chown
          - fchown
          - fchownat
          - lchown

    - name: Check existence of lchown in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_lchown
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_lchown_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_lchown_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+lchown[\s]+|([\s]+|[,])lchown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+lchown[\s]+|([\s]+|[,])lchown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_lchown_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_lchown_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+lchown[\s]+|([\s]+|[,])lchown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+lchown[\s]+|([\s]+|[,])lchown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_lchown_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_lchown_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+lchown[\s]+|([\s]+|[,])lchown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+lchown[\s]+|([\s]+|[,])lchown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_lchown_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_lchown_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+lchown[\s]+|([\s]+|[,])lchown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+lchown[\s]+|([\s]+|[,])lchown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_lchown_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_lchown_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+lchown[\s]+|([\s]+|[,])lchown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+lchown[\s]+|([\s]+|[,])lchown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_lchown_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_lchown_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+lchown[\s]+|([\s]+|[,])lchown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+lchown[\s]+|([\s]+|[,])lchown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_lchown_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_lchown_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+lchown[\s]+|([\s]+|[,])lchown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+lchown[\s]+|([\s]+|[,])lchown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_lchown_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_lchown_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+lchown[\s]+|([\s]+|[,])lchown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+lchown[\s]+|([\s]+|[,])lchown([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1
Record Unsuccessul Permission Changes to Files - lremovexattrxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_lremovexattr medium

Record Unsuccessul Permission Changes to Files - lremovexattr

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_lremovexattr
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_unsuccessful_file_modification_lremovexattr:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-000172, AU-2(d), AU-12(c), CM-6(a), SRG-OS-000458-VMM-001810, SRG-OS-000461-VMM-001830

Description
The audit system should collect unsuccessful file permission change attempts for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d. If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file.
-a always,exit -F arch=b32 -S lremovexattr -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
-a always,exit -F arch=b32 -S lremovexattr -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S lremovexattr -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
-a always,exit -F arch=b64 -S lremovexattr -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
Rationale
Unsuccessful attempts to change permissions of files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the audit rule checks a system call independently of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S chmod,fchmod,fchmodat,setxattr,lsetxattr,fsetxattr -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL="lremovexattr"
KEY="access"
SYSCALL_GROUPING=""

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EACCES"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EPERM"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_lremovexattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit lremovexattr tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_lremovexattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for lremovexattr EACCES for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lremovexattr
        syscall_grouping: []

    - name: Check existence of lremovexattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lremovexattr
        syscall_grouping: []

    - name: Check existence of lremovexattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_lremovexattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for lremovexattr EACCES for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lremovexattr
        syscall_grouping: []

    - name: Check existence of lremovexattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lremovexattr
        syscall_grouping: []

    - name: Check existence of lremovexattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_lremovexattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for lremovexattr EPERM for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lremovexattr
        syscall_grouping: []

    - name: Check existence of lremovexattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lremovexattr
        syscall_grouping: []

    - name: Check existence of lremovexattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_lremovexattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for lremovexattr EPERM for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lremovexattr
        syscall_grouping: []

    - name: Check existence of lremovexattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lremovexattr
        syscall_grouping: []

    - name: Check existence of lremovexattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_lremovexattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_lremovexattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_lremovexattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+lremovexattr[\s]+|([\s]+|[,])lremovexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+lremovexattr[\s]+|([\s]+|[,])lremovexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_lremovexattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_lremovexattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+lremovexattr[\s]+|([\s]+|[,])lremovexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+lremovexattr[\s]+|([\s]+|[,])lremovexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_lremovexattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_lremovexattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+lremovexattr[\s]+|([\s]+|[,])lremovexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+lremovexattr[\s]+|([\s]+|[,])lremovexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_lremovexattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_lremovexattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+lremovexattr[\s]+|([\s]+|[,])lremovexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+lremovexattr[\s]+|([\s]+|[,])lremovexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_lremovexattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_lremovexattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+lremovexattr[\s]+|([\s]+|[,])lremovexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+lremovexattr[\s]+|([\s]+|[,])lremovexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_lremovexattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_lremovexattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+lremovexattr[\s]+|([\s]+|[,])lremovexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+lremovexattr[\s]+|([\s]+|[,])lremovexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_lremovexattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_lremovexattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+lremovexattr[\s]+|([\s]+|[,])lremovexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+lremovexattr[\s]+|([\s]+|[,])lremovexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_lremovexattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_lremovexattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+lremovexattr[\s]+|([\s]+|[,])lremovexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+lremovexattr[\s]+|([\s]+|[,])lremovexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1
Record Unsuccessul Permission Changes to Files - lsetxattrxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_lsetxattr medium

Record Unsuccessul Permission Changes to Files - lsetxattr

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_lsetxattr
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_unsuccessful_file_modification_lsetxattr:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-000172, AU-2(d), AU-12(c), CM-6(a), SRG-OS-000458-VMM-001810, SRG-OS-000461-VMM-001830

Description
The audit system should collect unsuccessful file permission change attempts for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d. If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file.
-a always,exit -F arch=b32 -S lsetxattr -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
-a always,exit -F arch=b32 -S lsetxattr -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S lsetxattr -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
-a always,exit -F arch=b64 -S lsetxattr -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
Rationale
Unsuccessful attempts to change permissions of files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the audit rule checks a system call independently of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S chmod,fchmod,fchmodat,setxattr,lsetxattr,fsetxattr -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL="lsetxattr"
KEY="access"
SYSCALL_GROUPING="chmod fchmod fchmodat fsetxattr lsetxattr setxattr"

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EACCES"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EPERM"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_lsetxattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit lsetxattr tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_lsetxattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for lsetxattr EACCES for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lsetxattr
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of lsetxattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lsetxattr
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of lsetxattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_lsetxattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for lsetxattr EACCES for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lsetxattr
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of lsetxattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lsetxattr
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of lsetxattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_lsetxattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for lsetxattr EPERM for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lsetxattr
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of lsetxattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lsetxattr
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of lsetxattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_lsetxattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for lsetxattr EPERM for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lsetxattr
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of lsetxattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - lsetxattr
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of lsetxattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_lsetxattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_lsetxattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_lsetxattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+lsetxattr[\s]+|([\s]+|[,])lsetxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+lsetxattr[\s]+|([\s]+|[,])lsetxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_lsetxattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_lsetxattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+lsetxattr[\s]+|([\s]+|[,])lsetxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+lsetxattr[\s]+|([\s]+|[,])lsetxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_lsetxattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_lsetxattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+lsetxattr[\s]+|([\s]+|[,])lsetxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+lsetxattr[\s]+|([\s]+|[,])lsetxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_lsetxattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_lsetxattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+lsetxattr[\s]+|([\s]+|[,])lsetxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+lsetxattr[\s]+|([\s]+|[,])lsetxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_lsetxattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_lsetxattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+lsetxattr[\s]+|([\s]+|[,])lsetxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+lsetxattr[\s]+|([\s]+|[,])lsetxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_lsetxattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_lsetxattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+lsetxattr[\s]+|([\s]+|[,])lsetxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+lsetxattr[\s]+|([\s]+|[,])lsetxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_lsetxattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_lsetxattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+lsetxattr[\s]+|([\s]+|[,])lsetxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+lsetxattr[\s]+|([\s]+|[,])lsetxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_lsetxattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_lsetxattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+lsetxattr[\s]+|([\s]+|[,])lsetxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+lsetxattr[\s]+|([\s]+|[,])lsetxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1
Record Unsuccessful Access Attempts to Files - openxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_open medium

Record Unsuccessful Access Attempts to Files - open

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_open
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_unsuccessful_file_modification_open:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000130, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.2.4, Req-10.2.1, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000064-GPOS-00033, SRG-OS-000458-GPOS-00203, SRG-OS-000461-GPOS-00205, SRG-OS-000458-VMM-001810, SRG-OS-000461-VMM-001830

Description
At a minimum, the audit system should collect unauthorized file accesses for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S open -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S open -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S open -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S open -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S open -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S open -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S open -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S open -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
Rationale
Unsuccessful attempts to access files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL="open"
KEY="access"
SYSCALL_GROUPING="creat ftruncate truncate open openat open_by_handle_at"

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EACCES"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EPERM"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_open
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit open tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_open
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for open EACCES for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of open in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of open in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_open
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for open EACCES for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of open in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of open in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_open
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for open EPERM for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of open in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of open in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_open
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for open EPERM for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of open in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of open in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_open
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_open_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_open_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+open[\s]+|([\s]+|[,])open([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+open[\s]+|([\s]+|[,])open([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_open_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_open_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+open[\s]+|([\s]+|[,])open([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+open[\s]+|([\s]+|[,])open([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_open_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_open_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+open[\s]+|([\s]+|[,])open([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+open[\s]+|([\s]+|[,])open([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_open_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_open_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+open[\s]+|([\s]+|[,])open([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+open[\s]+|([\s]+|[,])open([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_open_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_open_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+open[\s]+|([\s]+|[,])open([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+open[\s]+|([\s]+|[,])open([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_open_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_open_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+open[\s]+|([\s]+|[,])open([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+open[\s]+|([\s]+|[,])open([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_open_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_open_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+open[\s]+|([\s]+|[,])open([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+open[\s]+|([\s]+|[,])open([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_open_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_open_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+open[\s]+|([\s]+|[,])open([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+open[\s]+|([\s]+|[,])open([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1
Record Unsuccessful Access Attempts to Files - open_by_handle_atxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_open_by_handle_at medium

Record Unsuccessful Access Attempts to Files - open_by_handle_at

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_open_by_handle_at
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_unsuccessful_file_modification_open_by_handle_at:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000130, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.2.4, Req-10.2.1, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000064-GPOS-00033, SRG-OS-000458-GPOS-00203, SRG-OS-000461-GPOS-00205, SRG-OS-000458-VMM-001810, SRG-OS-000461-VMM-001830

Description
At a minimum, the audit system should collect unauthorized file accesses for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S open_by_handle_at -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S open_by_handle_at -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S open_by_handle_at -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S open_by_handle_at -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S open_by_handle_at,truncate,ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S open_by_handle_at,truncate,ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S open_by_handle_at,truncate,ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S open_by_handle_at,truncate,ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
Rationale
Unsuccessful attempts to access files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL="open_by_handle_at"
KEY="access"
SYSCALL_GROUPING="creat ftruncate truncate open openat open_by_handle_at"

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EACCES"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EPERM"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_open_by_handle_at
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit open_by_handle_at tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_open_by_handle_at
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for open_by_handle_at EACCES for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open_by_handle_at
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of open_by_handle_at in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open_by_handle_at
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of open_by_handle_at in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_open_by_handle_at
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for open_by_handle_at EACCES for x86_64
    platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open_by_handle_at
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of open_by_handle_at in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open_by_handle_at
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of open_by_handle_at in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_open_by_handle_at
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for open_by_handle_at EPERM for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open_by_handle_at
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of open_by_handle_at in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open_by_handle_at
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of open_by_handle_at in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_open_by_handle_at
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for open_by_handle_at EPERM for x86_64
    platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open_by_handle_at
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of open_by_handle_at in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open_by_handle_at
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of open_by_handle_at in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_open_by_handle_at
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_open_by_handle_at_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_open_by_handle_at_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+open_by_handle_at[\s]+|([\s]+|[,])open_by_handle_at([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+open_by_handle_at[\s]+|([\s]+|[,])open_by_handle_at([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_open_by_handle_at_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_open_by_handle_at_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+open_by_handle_at[\s]+|([\s]+|[,])open_by_handle_at([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+open_by_handle_at[\s]+|([\s]+|[,])open_by_handle_at([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_open_by_handle_at_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_open_by_handle_at_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+open_by_handle_at[\s]+|([\s]+|[,])open_by_handle_at([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+open_by_handle_at[\s]+|([\s]+|[,])open_by_handle_at([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_open_by_handle_at_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_open_by_handle_at_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+open_by_handle_at[\s]+|([\s]+|[,])open_by_handle_at([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+open_by_handle_at[\s]+|([\s]+|[,])open_by_handle_at([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_open_by_handle_at_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_open_by_handle_at_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+open_by_handle_at[\s]+|([\s]+|[,])open_by_handle_at([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+open_by_handle_at[\s]+|([\s]+|[,])open_by_handle_at([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_open_by_handle_at_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_open_by_handle_at_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+open_by_handle_at[\s]+|([\s]+|[,])open_by_handle_at([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+open_by_handle_at[\s]+|([\s]+|[,])open_by_handle_at([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_open_by_handle_at_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_open_by_handle_at_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+open_by_handle_at[\s]+|([\s]+|[,])open_by_handle_at([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+open_by_handle_at[\s]+|([\s]+|[,])open_by_handle_at([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_open_by_handle_at_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_open_by_handle_at_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+open_by_handle_at[\s]+|([\s]+|[,])open_by_handle_at([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+open_by_handle_at[\s]+|([\s]+|[,])open_by_handle_at([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1
Record Unsuccessful Creation Attempts to Files - open_by_handle_at O_CREATxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_open_by_handle_at_o_creat medium

Record Unsuccessful Creation Attempts to Files - open_by_handle_at O_CREAT

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_open_by_handle_at_o_creat
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_unsuccessful_file_modification_open_by_handle_at_o_creat:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.2.4, Req-10.2.1, SRG-OS-000064-GPOS-00033, SRG-OS-000458-GPOS-00203, SRG-OS-000461-GPOS-00205, SRG-OS-000392-GPOS-00172, SRG-OS-000458-VMM-001810, SRG-OS-000461-VMM-001830

Description
The audit system should collect unauthorized file accesses for all users and root. The open_by_handle_at syscall can be used to create new files when O_CREAT flag is specified. The following auidt rules will asure that unsuccessful attempts to create a file via open_by_handle_at syscall are collected. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the rules below to a file with suffix .rules in the directory /etc/audit/rules.d. If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the rules below to /etc/audit/audit.rules file.
-a always,exit -F arch=b32 -S open_by_handle_at -F a2&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
-a always,exit -F arch=b32 -S open_by_handle_at -F a2&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S open_by_handle_at -F a2&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
-a always,exit -F arch=b64 -S open_by_handle_at -F a2&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
Rationale
Unsuccessful attempts to access files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_open_by_handle_at_o_creat
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Add unsuccessful file operations audit rules
  blockinfile:
    path: /etc/audit/rules.d/30-ospp-v42-remediation.rules
    create: true
    block: |-
      ## This content is a section of an Audit config snapshot recommended for Fedora systems that target OSPP compliance.
      ## The following content has been retreived on 2019-03-11 from: https://github.com/linux-audit/audit-userspace/blob/master/rules/30-ospp-v42.rules

      ## The purpose of these rules is to meet the requirements for Operating
      ## System Protection Profile (OSPP)v4.2. These rules depends on having
      ## 10-base-config.rules, 11-loginuid.rules, and 43-module-load.rules installed.

      ## Unsuccessful file creation (open with O_CREAT)
      -a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S openat,open_by_handle_at -F a2&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b32 -S open -F a1&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S open -F a1&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S openat,open_by_handle_at -F a2&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b32 -S open -F a1&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S open -F a1&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b32 -S creat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S creat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b32 -S creat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S creat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create

      ## Unsuccessful file modifications (open for write or truncate)
      -a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S openat,open_by_handle_at -F a2&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b32 -S open -F a1&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S open -F a1&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S openat,open_by_handle_at -F a2&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b32 -S open -F a1&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S open -F a1&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b32 -S truncate,ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S truncate,ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b32 -S truncate,ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S truncate,ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification

      ## Unsuccessful file access (any other opens) This has to go last.
      -a always,exit -F arch=b32 -S open,creat,truncate,ftruncate,openat,open_by_handle_at -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
      -a always,exit -F arch=b64 -S open,creat,truncate,ftruncate,openat,open_by_handle_at -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
      -a always,exit -F arch=b32 -S open,creat,truncate,ftruncate,openat,open_by_handle_at -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
      -a always,exit -F arch=b64 -S open,creat,truncate,ftruncate,openat,open_by_handle_at -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_open_by_handle_at_o_creat
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

defined audit rule must exist  oval:ssg-test_arufm_open_by_handle_at_o_creat_32bit_a20100_eacces_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_by_handle_at_o_creat_32bit_a20100_eacces_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+a2&0100)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

defined audit rule must exist  oval:ssg-test_arufm_open_by_handle_at_o_creat_32bit_a20100_eperm_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_by_handle_at_o_creat_32bit_a20100_eperm_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+a2&0100)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_arufm_open_by_handle_at_o_creat_64bit_a20100_eacces_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_by_handle_at_o_creat_64bit_a20100_eacces_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+a2&0100)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

defined audit rule must exist  oval:ssg-test_arufm_open_by_handle_at_o_creat_64bit_a20100_eperm_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_by_handle_at_o_creat_64bit_a20100_eperm_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+a2&0100)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

defined audit rule must exist  oval:ssg-test_arufm_open_by_handle_at_o_creat_32bit_a20100_eacces_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_by_handle_at_o_creat_32bit_a20100_eacces_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+a2&0100)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

defined audit rule must exist  oval:ssg-test_arufm_open_by_handle_at_o_creat_32bit_a20100_eperm_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_by_handle_at_o_creat_32bit_a20100_eperm_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+a2&0100)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_arufm_open_by_handle_at_o_creat_64bit_a20100_eacces_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_by_handle_at_o_creat_64bit_a20100_eacces_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+a2&0100)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

defined audit rule must exist  oval:ssg-test_arufm_open_by_handle_at_o_creat_64bit_a20100_eperm_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_by_handle_at_o_creat_64bit_a20100_eperm_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+a2&0100)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1
Record Unsuccessful Modification Attempts to Files - open_by_handle_at O_TRUNC_WRITExccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_open_by_handle_at_o_trunc_write medium

Record Unsuccessful Modification Attempts to Files - open_by_handle_at O_TRUNC_WRITE

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_open_by_handle_at_o_trunc_write
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_unsuccessful_file_modification_open_by_handle_at_o_trunc_write:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.2.4, Req-10.2.1, SRG-OS-000064-GPOS-00033, SRG-OS-000458-GPOS-00203, SRG-OS-000461-GPOS-00205, SRG-OS-000392-GPOS-00172, SRG-OS-000458-VMM-001810, SRG-OS-000461-VMM-001830

Description
The audit system should collect detailed unauthorized file accesses for all users and root. The open_by_handle_at syscall can be used to modify files if called for write operation of with O_TRUNC_WRITE flag. The following auidt rules will asure that unsuccessful attempts to modify a file via open_by_handle_at syscall are collected. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the rules below to a file with suffix .rules in the directory /etc/audit/rules.d. If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the rules below to /etc/audit/audit.rules file.
-a always,exit -F arch=b32 -S open_by_handle_at -F a2&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
-a always,exit -F arch=b32 -S open_by_handle_at -F a2&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S open_by_handle_at -F a2&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
-a always,exit -F arch=b64 -S open_by_handle_at -F a2&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
Rationale
Unsuccessful attempts to access files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_open_by_handle_at_o_trunc_write
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Add unsuccessful file operations audit rules
  blockinfile:
    path: /etc/audit/rules.d/30-ospp-v42-remediation.rules
    create: true
    block: |-
      ## This content is a section of an Audit config snapshot recommended for Fedora systems that target OSPP compliance.
      ## The following content has been retreived on 2019-03-11 from: https://github.com/linux-audit/audit-userspace/blob/master/rules/30-ospp-v42.rules

      ## The purpose of these rules is to meet the requirements for Operating
      ## System Protection Profile (OSPP)v4.2. These rules depends on having
      ## 10-base-config.rules, 11-loginuid.rules, and 43-module-load.rules installed.

      ## Unsuccessful file creation (open with O_CREAT)
      -a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S openat,open_by_handle_at -F a2&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b32 -S open -F a1&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S open -F a1&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S openat,open_by_handle_at -F a2&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b32 -S open -F a1&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S open -F a1&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b32 -S creat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S creat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b32 -S creat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S creat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create

      ## Unsuccessful file modifications (open for write or truncate)
      -a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S openat,open_by_handle_at -F a2&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b32 -S open -F a1&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S open -F a1&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S openat,open_by_handle_at -F a2&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b32 -S open -F a1&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S open -F a1&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b32 -S truncate,ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S truncate,ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b32 -S truncate,ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S truncate,ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification

      ## Unsuccessful file access (any other opens) This has to go last.
      -a always,exit -F arch=b32 -S open,creat,truncate,ftruncate,openat,open_by_handle_at -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
      -a always,exit -F arch=b64 -S open,creat,truncate,ftruncate,openat,open_by_handle_at -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
      -a always,exit -F arch=b32 -S open,creat,truncate,ftruncate,openat,open_by_handle_at -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
      -a always,exit -F arch=b64 -S open,creat,truncate,ftruncate,openat,open_by_handle_at -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_open_by_handle_at_o_trunc_write
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

defined audit rule must exist  oval:ssg-test_arufm_open_by_handle_at_o_trunc_32bit_a201003_eacces_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_by_handle_at_o_trunc_32bit_a201003_eacces_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+a2&01003)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

defined audit rule must exist  oval:ssg-test_arufm_open_by_handle_at_o_trunc_32bit_a201003_eperm_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_by_handle_at_o_trunc_32bit_a201003_eperm_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+a2&01003)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_arufm_open_by_handle_at_o_trunc_64bit_a201003_eacces_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_by_handle_at_o_trunc_64bit_a201003_eacces_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+a2&01003)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

defined audit rule must exist  oval:ssg-test_arufm_open_by_handle_at_o_trunc_64bit_a201003_eperm_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_by_handle_at_o_trunc_64bit_a201003_eperm_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+a2&01003)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

defined audit rule must exist  oval:ssg-test_arufm_open_by_handle_at_o_trunc_32bit_a201003_eacces_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_by_handle_at_o_trunc_32bit_a201003_eacces_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+a2&01003)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

defined audit rule must exist  oval:ssg-test_arufm_open_by_handle_at_o_trunc_32bit_a201003_eperm_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_by_handle_at_o_trunc_32bit_a201003_eperm_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+a2&01003)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_arufm_open_by_handle_at_o_trunc_64bit_a201003_eacces_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_by_handle_at_o_trunc_64bit_a201003_eacces_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+a2&01003)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

defined audit rule must exist  oval:ssg-test_arufm_open_by_handle_at_o_trunc_64bit_a201003_eperm_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_by_handle_at_o_trunc_64bit_a201003_eperm_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+a2&01003)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1
Ensure auditd Unauthorized Access Attempts To open_by_handle_at Are Ordered Correctlyxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_open_by_handle_at_rule_order medium

Ensure auditd Unauthorized Access Attempts To open_by_handle_at Are Ordered Correctly

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_open_by_handle_at_rule_order
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_unsuccessful_file_modification_open_by_handle_at_rule_order:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.2.4, Req-10.2.1, SRG-OS-000064-GPOS-00033, SRG-OS-000458-GPOS-00203, SRG-OS-000461-GPOS-00205, SRG-OS-000392-GPOS-00172, SRG-OS-000458-VMM-001810, SRG-OS-000461-VMM-001830

Description
The audit system should collect detailed unauthorized file accesses for all users and root. To correctly identify unsuccessful creation, unsuccessful modification and unsuccessful access of files via open_by_handle_at syscall the audit rules collecting these events need to be in certain order. The more specific rules need to come before the less specific rules. The reason for that is that more specific rules cover a subset of events covered in the less specific rules, thus, they need to come before to not be overshadowed by less specific rules, which match a bigger set of events. Make sure that rules for unsuccessful calls of open_by_handle_at syscall are in the order shown below. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), check the order of rules below in a file with suffix .rules in the directory /etc/audit/rules.d. If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, check the order of rules below in /etc/audit/audit.rules file.
-a always,exit -F arch=b32 -S open_by_handle_at -F a2&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
-a always,exit -F arch=b32 -S open_by_handle_at -F a2&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
-a always,exit -F arch=b32 -S open_by_handle_at -F a2&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
-a always,exit -F arch=b32 -S open_by_handle_at -F a2&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
-a always,exit -F arch=b32 -S open_by_handle_at -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
-a always,exit -F arch=b32 -S open_by_handle_at -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S open_by_handle_at -F a2&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
-a always,exit -F arch=b64 -S open_by_handle_at -F a2&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
-a always,exit -F arch=b64 -S open_by_handle_at -F a2&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
-a always,exit -F arch=b64 -S open_by_handle_at -F a2&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
-a always,exit -F arch=b64 -S open_by_handle_at -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
-a always,exit -F arch=b64 -S open_by_handle_at -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
Rationale
The more specific rules cover a subset of events covered by the less specific rules. By ordering them from more specific to less specific, it is assured that the less specific rule will not catch events better recorded by the more specific rule.
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

defined audit rule must exist  oval:ssg-test_arufm_open_by_handle_at_order_32bit_eacces_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_by_handle_at_order_32bit_eacces_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+a2&0100)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+a2&01003)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
Referenced variable has no values (oval:ssg-var_arufm_rule_order_32bit_open_by_handle_at_eacces_aug
^/etc/audit/rules\.d/.*\.rules$1

defined audit rule must exist  oval:ssg-test_arufm_open_by_handle_at_order_32bit_eperm_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_by_handle_at_order_32bit_eperm_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+a2&0100)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+a2&01003)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
Referenced variable has no values (oval:ssg-var_arufm_rule_order_32bit_open_by_handle_at_eperm_auge
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_arufm_open_by_handle_at_order_64bit_eacces_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_by_handle_at_order_64bit_eacces_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+a2&0100)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+a2&01003)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
Referenced variable has no values (oval:ssg-var_arufm_rule_order_64bit_open_by_handle_at_eacces_aug
^/etc/audit/rules\.d/.*\.rules$1

defined audit rule must exist  oval:ssg-test_arufm_open_by_handle_at_order_64bit_eperm_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_by_handle_at_order_64bit_eperm_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+a2&0100)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+a2&01003)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
Referenced variable has no values (oval:ssg-var_arufm_rule_order_64bit_open_by_handle_at_eperm_auge
^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

defined audit rule must exist  oval:ssg-test_arufm_open_by_handle_at_order_32bit_eacces_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_by_handle_at_order_32bit_eacces_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+a2&0100)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+a2&01003)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
Referenced variable has no values (oval:ssg-var_arufm_rule_order_32bit_open_by_handle_at_auditctl_e
^/etc/audit/rules\.d/.*\.rules$1

Test order of audit 32bit auditctl eperm rules order  oval:ssg-test_arufm_open_by_handle_at_order_32bit_eperm_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_by_handle_at_order_32bit_eperm_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+a2&0100)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+a2&01003)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
Referenced variable has no values (oval:ssg-var_arufm_rule_order_32bit_open_by_handle_at_auditctl_e
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_arufm_open_by_handle_at_order_64bit_eacces_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_by_handle_at_order_64bit_eacces_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+a2&0100)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+a2&01003)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
Referenced variable has no values (oval:ssg-var_arufm_open_by_handle_at_order_64bit_auditctl_eacces
^/etc/audit/rules\.d/.*\.rules$1

defined audit rule must exist  oval:ssg-test_arufm_open_by_handle_at_order_64bit_eperm_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_by_handle_at_order_64bit_eperm_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+a2&0100)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F\s+a2&01003)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
Referenced variable has no values (oval:ssg-var_arufm_rule_order_64bit_open_by_handle_at_auditctl_e
^/etc/audit/rules\.d/.*\.rules$1
Record Unsuccessful Creation Attempts to Files - open O_CREATxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_open_o_creat medium

Record Unsuccessful Creation Attempts to Files - open O_CREAT

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_open_o_creat
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_unsuccessful_file_modification_open_o_creat:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.2.4, Req-10.2.1, SRG-OS-000064-GPOS-00033, SRG-OS-000458-GPOS-00203, SRG-OS-000461-GPOS-00205, SRG-OS-000392-GPOS-00172, SRG-OS-000458-VMM-001810, SRG-OS-000461-VMM-001830

Description
The audit system should collect unauthorized file accesses for all users and root. The open syscall can be used to create new files when O_CREAT flag is specified. The following auidt rules will asure that unsuccessful attempts to create a file via open syscall are collected. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the rules below to a file with suffix .rules in the directory /etc/audit/rules.d. If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the rules below to /etc/audit/audit.rules file.
-a always,exit -F arch=b32 -S open -F a1&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
-a always,exit -F arch=b32 -S open -F a1&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S open -F a1&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
-a always,exit -F arch=b64 -S open -F a1&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
Rationale
Unsuccessful attempts to access files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S open -F a1&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_open_o_creat
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Add unsuccessful file operations audit rules
  blockinfile:
    path: /etc/audit/rules.d/30-ospp-v42-remediation.rules
    create: true
    block: |-
      ## This content is a section of an Audit config snapshot recommended for Fedora systems that target OSPP compliance.
      ## The following content has been retreived on 2019-03-11 from: https://github.com/linux-audit/audit-userspace/blob/master/rules/30-ospp-v42.rules

      ## The purpose of these rules is to meet the requirements for Operating
      ## System Protection Profile (OSPP)v4.2. These rules depends on having
      ## 10-base-config.rules, 11-loginuid.rules, and 43-module-load.rules installed.

      ## Unsuccessful file creation (open with O_CREAT)
      -a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S openat,open_by_handle_at -F a2&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b32 -S open -F a1&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S open -F a1&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S openat,open_by_handle_at -F a2&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b32 -S open -F a1&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S open -F a1&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b32 -S creat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S creat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b32 -S creat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S creat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create

      ## Unsuccessful file modifications (open for write or truncate)
      -a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S openat,open_by_handle_at -F a2&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b32 -S open -F a1&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S open -F a1&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S openat,open_by_handle_at -F a2&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b32 -S open -F a1&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S open -F a1&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b32 -S truncate,ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S truncate,ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b32 -S truncate,ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S truncate,ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification

      ## Unsuccessful file access (any other opens) This has to go last.
      -a always,exit -F arch=b32 -S open,creat,truncate,ftruncate,openat,open_by_handle_at -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
      -a always,exit -F arch=b64 -S open,creat,truncate,ftruncate,openat,open_by_handle_at -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
      -a always,exit -F arch=b32 -S open,creat,truncate,ftruncate,openat,open_by_handle_at -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
      -a always,exit -F arch=b64 -S open,creat,truncate,ftruncate,openat,open_by_handle_at -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_open_o_creat
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

defined audit rule must exist  oval:ssg-test_arufm_open_o_creat_32bit_a20100_eacces_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_o_creat_32bit_a20100_eacces_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+a1&0100)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

defined audit rule must exist  oval:ssg-test_arufm_open_o_creat_32bit_a20100_eperm_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_o_creat_32bit_a20100_eperm_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+a1&0100)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_arufm_open_o_creat_64bit_a20100_eacces_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_o_creat_64bit_a20100_eacces_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+a1&0100)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

defined audit rule must exist  oval:ssg-test_arufm_open_o_creat_64bit_a20100_eperm_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_o_creat_64bit_a20100_eperm_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+a1&0100)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

defined audit rule must exist  oval:ssg-test_arufm_open_o_creat_32bit_a20100_eacces_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_o_creat_32bit_a20100_eacces_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+a1&0100)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

defined audit rule must exist  oval:ssg-test_arufm_open_o_creat_32bit_a20100_eperm_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_o_creat_32bit_a20100_eperm_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+a1&0100)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_arufm_open_o_creat_64bit_a20100_eacces_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_o_creat_64bit_a20100_eacces_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+a1&0100)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

defined audit rule must exist  oval:ssg-test_arufm_open_o_creat_64bit_a20100_eperm_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_o_creat_64bit_a20100_eperm_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+a1&0100)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1
Record Unsuccessful Modification Attempts to Files - open O_TRUNC_WRITExccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_open_o_trunc_write medium

Record Unsuccessful Modification Attempts to Files - open O_TRUNC_WRITE

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_open_o_trunc_write
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_unsuccessful_file_modification_open_o_trunc_write:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.2.4, Req-10.2.1, SRG-OS-000064-GPOS-00033, SRG-OS-000458-GPOS-00203, SRG-OS-000461-GPOS-00205, SRG-OS-000392-GPOS-00172, SRG-OS-000458-VMM-001810, SRG-OS-000461-VMM-001830

Description
The audit system should collect detailed unauthorized file accesses for all users and root. The open syscall can be used to modify files if called for write operation of with O_TRUNC_WRITE flag. The following auidt rules will asure that unsuccessful attempts to modify a file via open syscall are collected. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the rules below to a file with suffix .rules in the directory /etc/audit/rules.d. If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the rules below to /etc/audit/audit.rules file.
-a always,exit -F arch=b32 -S open -F a1&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
-a always,exit -F arch=b32 -S open -F a1&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S open -F a1&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
-a always,exit -F arch=b64 -S open -F a1&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
Rationale
Unsuccessful attempts to access files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S open -F a1&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_open_o_trunc_write
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Add unsuccessful file operations audit rules
  blockinfile:
    path: /etc/audit/rules.d/30-ospp-v42-remediation.rules
    create: true
    block: |-
      ## This content is a section of an Audit config snapshot recommended for Fedora systems that target OSPP compliance.
      ## The following content has been retreived on 2019-03-11 from: https://github.com/linux-audit/audit-userspace/blob/master/rules/30-ospp-v42.rules

      ## The purpose of these rules is to meet the requirements for Operating
      ## System Protection Profile (OSPP)v4.2. These rules depends on having
      ## 10-base-config.rules, 11-loginuid.rules, and 43-module-load.rules installed.

      ## Unsuccessful file creation (open with O_CREAT)
      -a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S openat,open_by_handle_at -F a2&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b32 -S open -F a1&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S open -F a1&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S openat,open_by_handle_at -F a2&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b32 -S open -F a1&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S open -F a1&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b32 -S creat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S creat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b32 -S creat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S creat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create

      ## Unsuccessful file modifications (open for write or truncate)
      -a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S openat,open_by_handle_at -F a2&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b32 -S open -F a1&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S open -F a1&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S openat,open_by_handle_at -F a2&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b32 -S open -F a1&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S open -F a1&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b32 -S truncate,ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S truncate,ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b32 -S truncate,ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S truncate,ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification

      ## Unsuccessful file access (any other opens) This has to go last.
      -a always,exit -F arch=b32 -S open,creat,truncate,ftruncate,openat,open_by_handle_at -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
      -a always,exit -F arch=b64 -S open,creat,truncate,ftruncate,openat,open_by_handle_at -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
      -a always,exit -F arch=b32 -S open,creat,truncate,ftruncate,openat,open_by_handle_at -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
      -a always,exit -F arch=b64 -S open,creat,truncate,ftruncate,openat,open_by_handle_at -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_open_o_trunc_write
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

defined audit rule must exist  oval:ssg-test_arufm_open_o_trunc_32bit_a201003_eacces_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_o_trunc_32bit_a201003_eacces_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+a1&01003)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

defined audit rule must exist  oval:ssg-test_arufm_open_o_trunc_32bit_a201003_eperm_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_o_trunc_32bit_a201003_eperm_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+a1&01003)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_arufm_open_o_trunc_64bit_a201003_eacces_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_o_trunc_64bit_a201003_eacces_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+a1&01003)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

defined audit rule must exist  oval:ssg-test_arufm_open_o_trunc_64bit_a201003_eperm_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_o_trunc_64bit_a201003_eperm_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+a1&01003)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

defined audit rule must exist  oval:ssg-test_arufm_open_o_trunc_32bit_a201003_eacces_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_o_trunc_32bit_a201003_eacces_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+a1&01003)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

defined audit rule must exist  oval:ssg-test_arufm_open_o_trunc_32bit_a201003_eperm_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_o_trunc_32bit_a201003_eperm_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+a1&01003)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_arufm_open_o_trunc_64bit_a201003_eacces_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_o_trunc_64bit_a201003_eacces_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+a1&01003)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

defined audit rule must exist  oval:ssg-test_arufm_open_o_trunc_64bit_a201003_eperm_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_o_trunc_64bit_a201003_eperm_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+a1&01003)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1
Ensure auditd Rules For Unauthorized Attempts To open Are Ordered Correctlyxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_open_rule_order medium

Ensure auditd Rules For Unauthorized Attempts To open Are Ordered Correctly

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_open_rule_order
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_unsuccessful_file_modification_open_rule_order:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.2.4, Req-10.2.1, SRG-OS-000064-GPOS-00033, SRG-OS-000458-GPOS-00203, SRG-OS-000461-GPOS-00205, SRG-OS-000392-GPOS-00172, SRG-OS-000458-VMM-001810, SRG-OS-000461-VMM-001830

Description
The audit system should collect detailed unauthorized file accesses for all users and root. To correctly identify unsuccessful creation, unsuccessful modification and unsuccessful access of files via open syscall the audit rules collecting these events need to be in certain order. The more specific rules need to come before the less specific rules. The reason for that is that more specific rules cover a subset of events covered in the less specific rules, thus, they need to come before to not be overshadowed by less specific rules, which match a bigger set of events. Make sure that rules for unsuccessful calls of open syscall are in the order shown below. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), check the order of rules below in a file with suffix .rules in the directory /etc/audit/rules.d. If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, check the order of rules below in /etc/audit/audit.rules file.
-a always,exit -F arch=b32 -S open -F a1&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
-a always,exit -F arch=b32 -S open -F a1&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
-a always,exit -F arch=b32 -S open -F a1&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
-a always,exit -F arch=b32 -S open -F a1&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
-a always,exit -F arch=b32 -S open -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
-a always,exit -F arch=b32 -S open -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S open -F a1&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
-a always,exit -F arch=b64 -S open -F a1&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
-a always,exit -F arch=b64 -S open -F a1&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
-a always,exit -F arch=b64 -S open -F a1&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
-a always,exit -F arch=b64 -S open -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
-a always,exit -F arch=b64 -S open -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
Rationale
The more specific rules cover a subset of events covered by the less specific rules. By ordering them from more specific to less specific, it is assured that the less specific rule will not catch events better recorded by the more specific rule.
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

defined audit rule must exist  oval:ssg-test_arufm_open_order_32bit_eacces_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_order_32bit_eacces_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+a1&0100)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+a1&01003)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
Referenced variable has no values (oval:ssg-var_arufm_rule_order_32bit_open_eacces_augenrules_regex
^/etc/audit/rules\.d/.*\.rules$1

defined audit rule must exist  oval:ssg-test_arufm_open_order_32bit_eperm_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_order_32bit_eperm_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+a1&0100)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+a1&01003)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
Referenced variable has no values (oval:ssg-var_arufm_rule_order_32bit_open_eperm_augenrules_regex:
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_arufm_open_order_64bit_eacces_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_order_64bit_eacces_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+a1&0100)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+a1&01003)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
Referenced variable has no values (oval:ssg-var_arufm_rule_order_64bit_open_eacces_augenrules_regex
^/etc/audit/rules\.d/.*\.rules$1

defined audit rule must exist  oval:ssg-test_arufm_open_order_64bit_eperm_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_order_64bit_eperm_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+a1&0100)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+a1&01003)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
Referenced variable has no values (oval:ssg-var_arufm_rule_order_64bit_open_eperm_augenrules_regex:
^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

defined audit rule must exist  oval:ssg-test_arufm_open_order_32bit_eacces_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_order_32bit_eacces_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+a1&0100)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+a1&01003)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
Referenced variable has no values (oval:ssg-var_arufm_rule_order_32bit_open_auditctl_eacces_regex:v
^/etc/audit/rules\.d/.*\.rules$1

Test order of audit 32bit auditctl eperm rules order  oval:ssg-test_arufm_open_order_32bit_eperm_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_order_32bit_eperm_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+a1&0100)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+a1&01003)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
Referenced variable has no values (oval:ssg-var_arufm_rule_order_32bit_open_auditctl_eperm_regex:va
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_arufm_open_order_64bit_eacces_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_order_64bit_eacces_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+a1&0100)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+a1&01003)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
Referenced variable has no values (oval:ssg-var_arufm_open_order_64bit_auditctl_eacces_regex:var:1)
^/etc/audit/rules\.d/.*\.rules$1

defined audit rule must exist  oval:ssg-test_arufm_open_order_64bit_eperm_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_open_order_64bit_eperm_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+a1&0100)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F\s+a1&01003)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
Referenced variable has no values (oval:ssg-var_arufm_rule_order_64bit_open_auditctl_eperm_regex:va
^/etc/audit/rules\.d/.*\.rules$1
Record Unsuccessful Access Attempts to Files - openatxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_openat medium

Record Unsuccessful Access Attempts to Files - openat

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_openat
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_unsuccessful_file_modification_openat:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000130, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.2.4, Req-10.2.1, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000064-GPOS-00033, SRG-OS-000458-GPOS-00203, SRG-OS-000461-GPOS-00205, SRG-OS-000458-VMM-001810, SRG-OS-000461-VMM-001830

Description
At a minimum, the audit system should collect unauthorized file accesses for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S openat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S openat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S openat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S openat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S openat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S openat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S openat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S openat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
Rationale
Unsuccessful attempts to access files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL="openat"
KEY="access"
SYSCALL_GROUPING="creat ftruncate truncate open openat open_by_handle_at"

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EACCES"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EPERM"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_openat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit openat tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_openat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for openat EACCES for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - openat
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of openat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - openat
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of openat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_openat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for openat EACCES for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - openat
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of openat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - openat
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of openat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_openat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for openat EPERM for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - openat
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of openat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - openat
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of openat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_openat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for openat EPERM for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - openat
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of openat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - openat
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of openat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_openat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_openat_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_openat_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+openat[\s]+|([\s]+|[,])openat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+openat[\s]+|([\s]+|[,])openat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_openat_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_openat_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+openat[\s]+|([\s]+|[,])openat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+openat[\s]+|([\s]+|[,])openat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_openat_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_openat_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+openat[\s]+|([\s]+|[,])openat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+openat[\s]+|([\s]+|[,])openat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_openat_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_openat_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+openat[\s]+|([\s]+|[,])openat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+openat[\s]+|([\s]+|[,])openat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_openat_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_openat_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+openat[\s]+|([\s]+|[,])openat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+openat[\s]+|([\s]+|[,])openat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_openat_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_openat_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+openat[\s]+|([\s]+|[,])openat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+openat[\s]+|([\s]+|[,])openat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_openat_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_openat_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+openat[\s]+|([\s]+|[,])openat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+openat[\s]+|([\s]+|[,])openat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_openat_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_openat_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+openat[\s]+|([\s]+|[,])openat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+openat[\s]+|([\s]+|[,])openat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1
Record Unsuccessful Creation Attempts to Files - openat O_CREATxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_openat_o_creat medium

Record Unsuccessful Creation Attempts to Files - openat O_CREAT

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_openat_o_creat
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_unsuccessful_file_modification_openat_o_creat:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.2.4, Req-10.2.1, SRG-OS-000064-GPOS-00033, SRG-OS-000458-GPOS-00203, SRG-OS-000461-GPOS-00205, SRG-OS-000392-GPOS-00172, SRG-OS-000458-VMM-001810, SRG-OS-000461-VMM-001830

Description
The audit system should collect unauthorized file accesses for all users and root. The openat syscall can be used to create new files when O_CREAT flag is specified. The following auidt rules will asure that unsuccessful attempts to create a file via openat syscall are collected. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the rules below to a file with suffix .rules in the directory /etc/audit/rules.d. If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the rules below to /etc/audit/audit.rules file.
-a always,exit -F arch=b32 -S openat -F a2&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
-a always,exit -F arch=b32 -S openat -F a2&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S openat -F a2&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
-a always,exit -F arch=b64 -S openat -F a2&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
Rationale
Unsuccessful attempts to access files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_openat_o_creat
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Add unsuccessful file operations audit rules
  blockinfile:
    path: /etc/audit/rules.d/30-ospp-v42-remediation.rules
    create: true
    block: |-
      ## This content is a section of an Audit config snapshot recommended for Fedora systems that target OSPP compliance.
      ## The following content has been retreived on 2019-03-11 from: https://github.com/linux-audit/audit-userspace/blob/master/rules/30-ospp-v42.rules

      ## The purpose of these rules is to meet the requirements for Operating
      ## System Protection Profile (OSPP)v4.2. These rules depends on having
      ## 10-base-config.rules, 11-loginuid.rules, and 43-module-load.rules installed.

      ## Unsuccessful file creation (open with O_CREAT)
      -a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S openat,open_by_handle_at -F a2&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b32 -S open -F a1&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S open -F a1&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S openat,open_by_handle_at -F a2&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b32 -S open -F a1&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S open -F a1&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b32 -S creat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S creat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b32 -S creat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S creat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create

      ## Unsuccessful file modifications (open for write or truncate)
      -a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S openat,open_by_handle_at -F a2&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b32 -S open -F a1&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S open -F a1&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S openat,open_by_handle_at -F a2&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b32 -S open -F a1&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S open -F a1&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b32 -S truncate,ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S truncate,ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b32 -S truncate,ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S truncate,ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification

      ## Unsuccessful file access (any other opens) This has to go last.
      -a always,exit -F arch=b32 -S open,creat,truncate,ftruncate,openat,open_by_handle_at -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
      -a always,exit -F arch=b64 -S open,creat,truncate,ftruncate,openat,open_by_handle_at -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
      -a always,exit -F arch=b32 -S open,creat,truncate,ftruncate,openat,open_by_handle_at -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
      -a always,exit -F arch=b64 -S open,creat,truncate,ftruncate,openat,open_by_handle_at -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_openat_o_creat
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

defined audit rule must exist  oval:ssg-test_arufm_openat_o_creat_32bit_a20100_eacces_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_openat_o_creat_32bit_a20100_eacces_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+a2&0100)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

defined audit rule must exist  oval:ssg-test_arufm_openat_o_creat_32bit_a20100_eperm_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_openat_o_creat_32bit_a20100_eperm_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+a2&0100)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_arufm_openat_o_creat_64bit_a20100_eacces_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_openat_o_creat_64bit_a20100_eacces_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+a2&0100)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

defined audit rule must exist  oval:ssg-test_arufm_openat_o_creat_64bit_a20100_eperm_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_openat_o_creat_64bit_a20100_eperm_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+a2&0100)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

defined audit rule must exist  oval:ssg-test_arufm_openat_o_creat_32bit_a20100_eacces_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_openat_o_creat_32bit_a20100_eacces_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+a2&0100)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

defined audit rule must exist  oval:ssg-test_arufm_openat_o_creat_32bit_a20100_eperm_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_openat_o_creat_32bit_a20100_eperm_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+a2&0100)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_arufm_openat_o_creat_64bit_a20100_eacces_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_openat_o_creat_64bit_a20100_eacces_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+a2&0100)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

defined audit rule must exist  oval:ssg-test_arufm_openat_o_creat_64bit_a20100_eperm_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_openat_o_creat_64bit_a20100_eperm_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+a2&0100)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1
Record Unsuccessful Modification Attempts to Files - openat O_TRUNC_WRITExccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_openat_o_trunc_write medium

Record Unsuccessful Modification Attempts to Files - openat O_TRUNC_WRITE

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_openat_o_trunc_write
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_unsuccessful_file_modification_openat_o_trunc_write:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.2.4, Req-10.2.1, SRG-OS-000064-GPOS-00033, SRG-OS-000458-GPOS-00203, SRG-OS-000461-GPOS-00205, SRG-OS-000392-GPOS-00172, SRG-OS-000458-VMM-001810, SRG-OS-000461-VMM-001830

Description
The audit system should collect detailed unauthorized file accesses for all users and root. The openat syscall can be used to modify files if called for write operation of with O_TRUNC_WRITE flag. The following auidt rules will asure that unsuccessful attempts to modify a file via openat syscall are collected. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the rules below to a file with suffix .rules in the directory /etc/audit/rules.d. If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the rules below to /etc/audit/audit.rules file.
-a always,exit -F arch=b32 -S openat -F a2&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
-a always,exit -F arch=b32 -S openat -F a2&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S openat -F a2&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
-a always,exit -F arch=b64 -S openat -F a2&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
Rationale
Unsuccessful attempts to access files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_openat_o_trunc_write
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Add unsuccessful file operations audit rules
  blockinfile:
    path: /etc/audit/rules.d/30-ospp-v42-remediation.rules
    create: true
    block: |-
      ## This content is a section of an Audit config snapshot recommended for Fedora systems that target OSPP compliance.
      ## The following content has been retreived on 2019-03-11 from: https://github.com/linux-audit/audit-userspace/blob/master/rules/30-ospp-v42.rules

      ## The purpose of these rules is to meet the requirements for Operating
      ## System Protection Profile (OSPP)v4.2. These rules depends on having
      ## 10-base-config.rules, 11-loginuid.rules, and 43-module-load.rules installed.

      ## Unsuccessful file creation (open with O_CREAT)
      -a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S openat,open_by_handle_at -F a2&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b32 -S open -F a1&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S open -F a1&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S openat,open_by_handle_at -F a2&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b32 -S open -F a1&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S open -F a1&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b32 -S creat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S creat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b32 -S creat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
      -a always,exit -F arch=b64 -S creat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create

      ## Unsuccessful file modifications (open for write or truncate)
      -a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S openat,open_by_handle_at -F a2&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b32 -S open -F a1&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S open -F a1&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S openat,open_by_handle_at -F a2&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b32 -S open -F a1&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S open -F a1&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b32 -S truncate,ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S truncate,ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b32 -S truncate,ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
      -a always,exit -F arch=b64 -S truncate,ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification

      ## Unsuccessful file access (any other opens) This has to go last.
      -a always,exit -F arch=b32 -S open,creat,truncate,ftruncate,openat,open_by_handle_at -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
      -a always,exit -F arch=b64 -S open,creat,truncate,ftruncate,openat,open_by_handle_at -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
      -a always,exit -F arch=b32 -S open,creat,truncate,ftruncate,openat,open_by_handle_at -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
      -a always,exit -F arch=b64 -S open,creat,truncate,ftruncate,openat,open_by_handle_at -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_openat_o_trunc_write
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

defined audit rule must exist  oval:ssg-test_arufm_openat_o_trunc_32bit_a201003_eacces_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_openat_o_trunc_32bit_a201003_eacces_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+a2&01003)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

defined audit rule must exist  oval:ssg-test_arufm_openat_o_trunc_32bit_a201003_eperm_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_openat_o_trunc_32bit_a201003_eperm_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+a2&01003)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_arufm_openat_o_trunc_64bit_a201003_eacces_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_openat_o_trunc_64bit_a201003_eacces_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+a2&01003)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

defined audit rule must exist  oval:ssg-test_arufm_openat_o_trunc_64bit_a201003_eperm_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_openat_o_trunc_64bit_a201003_eperm_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+a2&01003)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

defined audit rule must exist  oval:ssg-test_arufm_openat_o_trunc_32bit_a201003_eacces_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_openat_o_trunc_32bit_a201003_eacces_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+a2&01003)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

defined audit rule must exist  oval:ssg-test_arufm_openat_o_trunc_32bit_a201003_eperm_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_openat_o_trunc_32bit_a201003_eperm_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+a2&01003)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_arufm_openat_o_trunc_64bit_a201003_eacces_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_openat_o_trunc_64bit_a201003_eacces_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+a2&01003)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

defined audit rule must exist  oval:ssg-test_arufm_openat_o_trunc_64bit_a201003_eperm_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_openat_o_trunc_64bit_a201003_eperm_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+a2&01003)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1
Ensure auditd Rules For Unauthorized Attempts To openat Are Ordered Correctlyxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_openat_rule_order medium

Ensure auditd Rules For Unauthorized Attempts To openat Are Ordered Correctly

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_openat_rule_order
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_unsuccessful_file_modification_openat_rule_order:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.2.4, Req-10.2.1, SRG-OS-000064-GPOS-00033, SRG-OS-000458-GPOS-00203, SRG-OS-000461-GPOS-00205, SRG-OS-000392-GPOS-00172, SRG-OS-000458-VMM-001810, SRG-OS-000461-VMM-001830

Description
The audit system should collect detailed unauthorized file accesses for all users and root. To correctly identify unsuccessful creation, unsuccessful modification and unsuccessful access of files via openat syscall the audit rules collecting these events need to be in certain order. The more specific rules need to come before the less specific rules. The reason for that is that more specific rules cover a subset of events covered in the less specific rules, thus, they need to come before to not be overshadowed by less specific rules, which match a bigger set of events. Make sure that rules for unsuccessful calls of openat syscall are in the order shown below. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), check the order of rules below in a file with suffix .rules in the directory /etc/audit/rules.d. If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, check the order of rules below in /etc/audit/audit.rules file.
-a always,exit -F arch=b32 -S openat -F a2&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
-a always,exit -F arch=b32 -S openat -F a2&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
-a always,exit -F arch=b32 -S openat -F a2&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
-a always,exit -F arch=b32 -S openat -F a2&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
-a always,exit -F arch=b32 -S openat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
-a always,exit -F arch=b32 -S openat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S openat -F a2&0100 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
-a always,exit -F arch=b64 -S openat -F a2&0100 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-create
-a always,exit -F arch=b64 -S openat -F a2&01003 -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
-a always,exit -F arch=b64 -S openat -F a2&01003 -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-modification
-a always,exit -F arch=b64 -S openat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
-a always,exit -F arch=b64 -S openat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-access
Rationale
The more specific rules cover a subset of events covered by the less specific rules. By ordering them from more specific to less specific, it is assured that the less specific rule will not catch events better recorded by the more specific rule.
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

defined audit rule must exist  oval:ssg-test_arufm_openat_order_32bit_eacces_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_openat_order_32bit_eacces_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+a2&0100)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+a2&01003)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
Referenced variable has no values (oval:ssg-var_arufm_rule_order_32bit_openat_eacces_augenrules_reg
^/etc/audit/rules\.d/.*\.rules$1

defined audit rule must exist  oval:ssg-test_arufm_openat_order_32bit_eperm_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_openat_order_32bit_eperm_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+a2&0100)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+a2&01003)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
Referenced variable has no values (oval:ssg-var_arufm_rule_order_32bit_openat_eperm_augenrules_rege
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_arufm_openat_order_64bit_eacces_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_openat_order_64bit_eacces_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+a2&0100)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+a2&01003)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
Referenced variable has no values (oval:ssg-var_arufm_rule_order_64bit_openat_eacces_augenrules_reg
^/etc/audit/rules\.d/.*\.rules$1

defined audit rule must exist  oval:ssg-test_arufm_openat_order_64bit_eperm_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_openat_order_64bit_eperm_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+a2&0100)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+a2&01003)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
Referenced variable has no values (oval:ssg-var_arufm_rule_order_64bit_openat_eperm_augenrules_rege
^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

defined audit rule must exist  oval:ssg-test_arufm_openat_order_32bit_eacces_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_openat_order_32bit_eacces_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+a2&0100)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+a2&01003)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
Referenced variable has no values (oval:ssg-var_arufm_rule_order_32bit_openat_auditctl_eacces_regex
^/etc/audit/rules\.d/.*\.rules$1

Test order of audit 32bit auditctl eperm rules order  oval:ssg-test_arufm_openat_order_32bit_eperm_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_openat_order_32bit_eperm_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+a2&0100)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+a2&01003)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
Referenced variable has no values (oval:ssg-var_arufm_rule_order_32bit_openat_auditctl_eperm_regex:
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_arufm_openat_order_64bit_eacces_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_openat_order_64bit_eacces_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+a2&0100)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+a2&01003)[\s]+(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
Referenced variable has no values (oval:ssg-var_arufm_openat_order_64bit_auditctl_eacces_regex:var:
^/etc/audit/rules\.d/.*\.rules$1

defined audit rule must exist  oval:ssg-test_arufm_openat_order_64bit_eperm_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arufm_openat_order_64bit_eperm_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+a2&0100)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F\s+a2&01003)[\s]+(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(?:unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
Referenced variable has no values (oval:ssg-var_arufm_rule_order_64bit_openat_auditctl_eperm_regex:
^/etc/audit/rules\.d/.*\.rules$1
Record Unsuccessul Permission Changes to Files - removexattrxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_removexattr medium

Record Unsuccessul Permission Changes to Files - removexattr

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_removexattr
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_unsuccessful_file_modification_removexattr:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-000172, AU-2(d), AU-12(c), CM-6(a), SRG-OS-000458-VMM-001810, SRG-OS-000461-VMM-001830

Description
The audit system should collect unsuccessful file permission change attempts for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d. If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file.
-a always,exit -F arch=b32 -S removexattr -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
-a always,exit -F arch=b32 -S removexattr -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S removexattr -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
-a always,exit -F arch=b64 -S removexattr -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
Rationale
Unsuccessful attempts to change permissions of files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the audit rule checks a system call independently of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S chmod,fchmod,fchmodat,setxattr,lsetxattr,fsetxattr -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL="removexattr"
KEY="access"
SYSCALL_GROUPING=""

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EACCES"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EPERM"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_removexattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit removexattr tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_removexattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for removexattr EACCES for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - removexattr
        syscall_grouping: []

    - name: Check existence of removexattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - removexattr
        syscall_grouping: []

    - name: Check existence of removexattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_removexattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for removexattr EACCES for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - removexattr
        syscall_grouping: []

    - name: Check existence of removexattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - removexattr
        syscall_grouping: []

    - name: Check existence of removexattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_removexattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for removexattr EPERM for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - removexattr
        syscall_grouping: []

    - name: Check existence of removexattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - removexattr
        syscall_grouping: []

    - name: Check existence of removexattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_removexattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for removexattr EPERM for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - removexattr
        syscall_grouping: []

    - name: Check existence of removexattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - removexattr
        syscall_grouping: []

    - name: Check existence of removexattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_removexattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_removexattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_removexattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+removexattr[\s]+|([\s]+|[,])removexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+removexattr[\s]+|([\s]+|[,])removexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_removexattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_removexattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+removexattr[\s]+|([\s]+|[,])removexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+removexattr[\s]+|([\s]+|[,])removexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_removexattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_removexattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+removexattr[\s]+|([\s]+|[,])removexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+removexattr[\s]+|([\s]+|[,])removexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_removexattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_removexattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+removexattr[\s]+|([\s]+|[,])removexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+removexattr[\s]+|([\s]+|[,])removexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_removexattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_removexattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+removexattr[\s]+|([\s]+|[,])removexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+removexattr[\s]+|([\s]+|[,])removexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_removexattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_removexattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+removexattr[\s]+|([\s]+|[,])removexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+removexattr[\s]+|([\s]+|[,])removexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_removexattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_removexattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+removexattr[\s]+|([\s]+|[,])removexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+removexattr[\s]+|([\s]+|[,])removexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_removexattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_removexattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+removexattr[\s]+|([\s]+|[,])removexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+removexattr[\s]+|([\s]+|[,])removexattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1
Record Unsuccessul Delete Attempts to Files - renamexccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_rename medium

Record Unsuccessul Delete Attempts to Files - rename

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_rename
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_unsuccessful_file_modification_rename:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.2.4, Req-10.2.1, SRG-OS-000064-GPOS-00033, SRG-OS-000392-GPOS-00172, SRG-OS-000458-GPOS-00203, SRG-OS-000461-GPOS-00205, SRG-OS-000468-GPOS-00212, SRG-OS-000458-VMM-001810, SRG-OS-000461-VMM-001830

Description
The audit system should collect unsuccessful file deletion attempts for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d. If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file.
-a always,exit -F arch=b32 -S rename -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccessful-delete
-a always,exit -F arch=b32 -S rename -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccessful-delete
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S rename -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccessful-delete
-a always,exit -F arch=b64 -S rename -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccessful-delete
Rationale
Unsuccessful attempts to delete files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S unlink,unlinkat,rename,renameat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-delete

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL="rename"
KEY="access"
SYSCALL_GROUPING="rename renameat unlink unlinkat"

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EACCES"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EPERM"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_rename
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit rename tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_rename
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for rename EACCES for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - rename
        syscall_grouping:
          - rename
          - renameat
          - unlink
          - unlinkat

    - name: Check existence of rename in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - rename
        syscall_grouping:
          - rename
          - renameat
          - unlink
          - unlinkat

    - name: Check existence of rename in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_rename
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for rename EACCES for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - rename
        syscall_grouping:
          - rename
          - renameat
          - unlink
          - unlinkat

    - name: Check existence of rename in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - rename
        syscall_grouping:
          - rename
          - renameat
          - unlink
          - unlinkat

    - name: Check existence of rename in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_rename
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for rename EPERM for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - rename
        syscall_grouping:
          - rename
          - renameat
          - unlink
          - unlinkat

    - name: Check existence of rename in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - rename
        syscall_grouping:
          - rename
          - renameat
          - unlink
          - unlinkat

    - name: Check existence of rename in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_rename
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for rename EPERM for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - rename
        syscall_grouping:
          - rename
          - renameat
          - unlink
          - unlinkat

    - name: Check existence of rename in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - rename
        syscall_grouping:
          - rename
          - renameat
          - unlink
          - unlinkat

    - name: Check existence of rename in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_rename
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_rename_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_rename_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+rename[\s]+|([\s]+|[,])rename([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+rename[\s]+|([\s]+|[,])rename([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_rename_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_rename_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+rename[\s]+|([\s]+|[,])rename([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+rename[\s]+|([\s]+|[,])rename([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_rename_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_rename_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+rename[\s]+|([\s]+|[,])rename([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+rename[\s]+|([\s]+|[,])rename([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_rename_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_rename_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+rename[\s]+|([\s]+|[,])rename([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+rename[\s]+|([\s]+|[,])rename([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_rename_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_rename_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+rename[\s]+|([\s]+|[,])rename([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+rename[\s]+|([\s]+|[,])rename([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_rename_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_rename_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+rename[\s]+|([\s]+|[,])rename([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+rename[\s]+|([\s]+|[,])rename([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_rename_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_rename_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+rename[\s]+|([\s]+|[,])rename([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+rename[\s]+|([\s]+|[,])rename([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_rename_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_rename_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+rename[\s]+|([\s]+|[,])rename([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+rename[\s]+|([\s]+|[,])rename([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1
Record Unsuccessul Delete Attempts to Files - renameatxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_renameat medium

Record Unsuccessul Delete Attempts to Files - renameat

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_renameat
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_unsuccessful_file_modification_renameat:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.2.4, Req-10.2.1, SRG-OS-000064-GPOS-00033, SRG-OS-000392-GPOS-00172, SRG-OS-000458-GPOS-00203, SRG-OS-000461-GPOS-00205, SRG-OS-000468-GPOS-00212, SRG-OS-000458-VMM-001810, SRG-OS-000461-VMM-001830

Description
The audit system should collect unsuccessful file deletion attempts for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d. If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file.
-a always,exit -F arch=b32 -S renameat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccessful-delete
-a always,exit -F arch=b32 -S renameat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccessful-delete
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S renameat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccessful-delete
-a always,exit -F arch=b64 -S renameat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccessful-delete
Rationale
Unsuccessful attempts to delete files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S unlink,unlinkat,rename,renameat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-delete

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL="renameat"
KEY="access"
SYSCALL_GROUPING="rename renameat unlink unlinkat"

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EACCES"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EPERM"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_renameat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit renameat tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_renameat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for renameat EACCES for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - renameat
        syscall_grouping:
          - rename
          - renameat
          - unlink
          - unlinkat

    - name: Check existence of renameat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - renameat
        syscall_grouping:
          - rename
          - renameat
          - unlink
          - unlinkat

    - name: Check existence of renameat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_renameat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for renameat EACCES for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - renameat
        syscall_grouping:
          - rename
          - renameat
          - unlink
          - unlinkat

    - name: Check existence of renameat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - renameat
        syscall_grouping:
          - rename
          - renameat
          - unlink
          - unlinkat

    - name: Check existence of renameat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_renameat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for renameat EPERM for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - renameat
        syscall_grouping:
          - rename
          - renameat
          - unlink
          - unlinkat

    - name: Check existence of renameat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - renameat
        syscall_grouping:
          - rename
          - renameat
          - unlink
          - unlinkat

    - name: Check existence of renameat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_renameat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for renameat EPERM for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - renameat
        syscall_grouping:
          - rename
          - renameat
          - unlink
          - unlinkat

    - name: Check existence of renameat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - renameat
        syscall_grouping:
          - rename
          - renameat
          - unlink
          - unlinkat

    - name: Check existence of renameat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_renameat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_renameat_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_renameat_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+renameat[\s]+|([\s]+|[,])renameat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+renameat[\s]+|([\s]+|[,])renameat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_renameat_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_renameat_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+renameat[\s]+|([\s]+|[,])renameat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+renameat[\s]+|([\s]+|[,])renameat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_renameat_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_renameat_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+renameat[\s]+|([\s]+|[,])renameat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+renameat[\s]+|([\s]+|[,])renameat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_renameat_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_renameat_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+renameat[\s]+|([\s]+|[,])renameat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+renameat[\s]+|([\s]+|[,])renameat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_renameat_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_renameat_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+renameat[\s]+|([\s]+|[,])renameat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+renameat[\s]+|([\s]+|[,])renameat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_renameat_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_renameat_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+renameat[\s]+|([\s]+|[,])renameat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+renameat[\s]+|([\s]+|[,])renameat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_renameat_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_renameat_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+renameat[\s]+|([\s]+|[,])renameat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+renameat[\s]+|([\s]+|[,])renameat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_renameat_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_renameat_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+renameat[\s]+|([\s]+|[,])renameat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+renameat[\s]+|([\s]+|[,])renameat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1
Record Unsuccessul Permission Changes to Files - setxattrxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_setxattr medium

Record Unsuccessul Permission Changes to Files - setxattr

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_setxattr
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_unsuccessful_file_modification_setxattr:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-000172, AU-2(d), AU-12(c), CM-6(a), SRG-OS-000458-VMM-001810, SRG-OS-000461-VMM-001830

Description
The audit system should collect unsuccessful file permission change attempts for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d. If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file.
-a always,exit -F arch=b32 -S setxattr -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
-a always,exit -F arch=b32 -S setxattr -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S setxattr -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
-a always,exit -F arch=b64 -S setxattr -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
Rationale
Unsuccessful attempts to change permissions of files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the audit rule checks a system call independently of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S chmod,fchmod,fchmodat,setxattr,lsetxattr,fsetxattr -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL="setxattr"
KEY="access"
SYSCALL_GROUPING="chmod fchmod fchmodat fsetxattr lsetxattr setxattr"

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EACCES"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EPERM"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_setxattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit setxattr tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_setxattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for setxattr EACCES for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - setxattr
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of setxattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - setxattr
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of setxattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_setxattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for setxattr EACCES for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - setxattr
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of setxattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - setxattr
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of setxattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_setxattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for setxattr EPERM for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - setxattr
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of setxattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - setxattr
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of setxattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_setxattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for setxattr EPERM for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - setxattr
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of setxattr in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - setxattr
        syscall_grouping:
          - chmod
          - fchmod
          - fchmodat
          - fsetxattr
          - lsetxattr
          - setxattr

    - name: Check existence of setxattr in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_unsuccessful_file_modification_setxattr
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_setxattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_setxattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+setxattr[\s]+|([\s]+|[,])setxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+setxattr[\s]+|([\s]+|[,])setxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_setxattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_setxattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+setxattr[\s]+|([\s]+|[,])setxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+setxattr[\s]+|([\s]+|[,])setxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_setxattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_setxattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+setxattr[\s]+|([\s]+|[,])setxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+setxattr[\s]+|([\s]+|[,])setxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_setxattr_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_setxattr_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+setxattr[\s]+|([\s]+|[,])setxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+setxattr[\s]+|([\s]+|[,])setxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_setxattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_setxattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+setxattr[\s]+|([\s]+|[,])setxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+setxattr[\s]+|([\s]+|[,])setxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_setxattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_setxattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+setxattr[\s]+|([\s]+|[,])setxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+setxattr[\s]+|([\s]+|[,])setxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_setxattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_setxattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+setxattr[\s]+|([\s]+|[,])setxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+setxattr[\s]+|([\s]+|[,])setxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_setxattr_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_setxattr_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+setxattr[\s]+|([\s]+|[,])setxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+setxattr[\s]+|([\s]+|[,])setxattr([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1
Record Unsuccessful Access Attempts to Files - truncatexccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_truncate medium

Record Unsuccessful Access Attempts to Files - truncate

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_truncate
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_unsuccessful_file_modification_truncate:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.2.4, Req-10.2.1, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000064-GPOS-00033, SRG-OS-000458-GPOS-00203, SRG-OS-000461-GPOS-00205, SRG-OS-000458-VMM-001810, SRG-OS-000461-VMM-001830

Description
At a minimum, the audit system should collect unauthorized file accesses for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S truncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S truncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S truncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S truncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S truncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S truncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S truncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S truncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
Rationale
Unsuccessful attempts to access files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL="truncate"
KEY="access"
SYSCALL_GROUPING="creat ftruncate truncate open openat open_by_handle_at"

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EACCES"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EPERM"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_truncate
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit truncate tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_truncate
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for truncate EACCES for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - truncate
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of truncate in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - truncate
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of truncate in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_truncate
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for truncate EACCES for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - truncate
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of truncate in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - truncate
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of truncate in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_truncate
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for truncate EPERM for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - truncate
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of truncate in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - truncate
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of truncate in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_truncate
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for truncate EPERM for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - truncate
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of truncate in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - truncate
        syscall_grouping:
          - creat
          - ftruncate
          - truncate
          - open
          - openat
          - open_by_handle_at

    - name: Check existence of truncate in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_truncate
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_truncate_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_truncate_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+truncate[\s]+|([\s]+|[,])truncate([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+truncate[\s]+|([\s]+|[,])truncate([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_truncate_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_truncate_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+truncate[\s]+|([\s]+|[,])truncate([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+truncate[\s]+|([\s]+|[,])truncate([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_truncate_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_truncate_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+truncate[\s]+|([\s]+|[,])truncate([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+truncate[\s]+|([\s]+|[,])truncate([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_truncate_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_truncate_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+truncate[\s]+|([\s]+|[,])truncate([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+truncate[\s]+|([\s]+|[,])truncate([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_truncate_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_truncate_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+truncate[\s]+|([\s]+|[,])truncate([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+truncate[\s]+|([\s]+|[,])truncate([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_truncate_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_truncate_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+truncate[\s]+|([\s]+|[,])truncate([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+truncate[\s]+|([\s]+|[,])truncate([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_truncate_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_truncate_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+truncate[\s]+|([\s]+|[,])truncate([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+truncate[\s]+|([\s]+|[,])truncate([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_truncate_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_truncate_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+truncate[\s]+|([\s]+|[,])truncate([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+truncate[\s]+|([\s]+|[,])truncate([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1
Record Unsuccessul Delete Attempts to Files - unlinkatxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_unlinkat medium

Record Unsuccessul Delete Attempts to Files - unlinkat

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_unlinkat
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_unsuccessful_file_modification_unlinkat:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.2.4, Req-10.2.1, SRG-OS-000064-GPOS-00033, SRG-OS-000392-GPOS-00172, SRG-OS-000458-GPOS-00203, SRG-OS-000461-GPOS-00205, SRG-OS-000468-GPOS-00212, SRG-OS-000458-VMM-001810, SRG-OS-000461-VMM-001830

Description
The audit system should collect unsuccessful file deletion attempts for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d. If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file.
-a always,exit -F arch=b32 -S unlinkat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccessful-delete
-a always,exit -F arch=b32 -S unlinkat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccessful-delete
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S unlinkat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccessful-delete
-a always,exit -F arch=b64 -S unlinkat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=unsuccessful-delete
Rationale
Unsuccessful attempts to delete files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S unlink,unlinkat,rename,renameat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-delete

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL="unlinkat"
KEY="access"
SYSCALL_GROUPING="rename renameat unlink unlinkat"

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EACCES"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EPERM"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_unlinkat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit unlinkat tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_unlinkat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for unlinkat EACCES for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - unlinkat
        syscall_grouping:
          - rename
          - renameat
          - unlink
          - unlinkat

    - name: Check existence of unlinkat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - unlinkat
        syscall_grouping:
          - rename
          - renameat
          - unlink
          - unlinkat

    - name: Check existence of unlinkat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_unlinkat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for unlinkat EACCES for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - unlinkat
        syscall_grouping:
          - rename
          - renameat
          - unlink
          - unlinkat

    - name: Check existence of unlinkat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - unlinkat
        syscall_grouping:
          - rename
          - renameat
          - unlink
          - unlinkat

    - name: Check existence of unlinkat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_unlinkat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for unlinkat EPERM for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - unlinkat
        syscall_grouping:
          - rename
          - renameat
          - unlink
          - unlinkat

    - name: Check existence of unlinkat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - unlinkat
        syscall_grouping:
          - rename
          - renameat
          - unlink
          - unlinkat

    - name: Check existence of unlinkat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_unlinkat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for unlinkat EPERM for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - unlinkat
        syscall_grouping:
          - rename
          - renameat
          - unlink
          - unlinkat

    - name: Check existence of unlinkat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
      set_fact: audit_file="/etc/audit/rules.d/access.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - unlinkat
        syscall_grouping:
          - rename
          - renameat
          - unlink
          - unlinkat

    - name: Check existence of unlinkat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
          -F auid>=1000 -F auid!=unset -F key=access
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.1
    - PCI-DSS-Req-10.2.4
    - audit_rules_unsuccessful_file_modification_unlinkat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_unlinkat_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_unlinkat_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+unlinkat[\s]+|([\s]+|[,])unlinkat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+unlinkat[\s]+|([\s]+|[,])unlinkat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_unlinkat_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_unlinkat_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+unlinkat[\s]+|([\s]+|[,])unlinkat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+unlinkat[\s]+|([\s]+|[,])unlinkat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_unlinkat_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_unlinkat_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+unlinkat[\s]+|([\s]+|[,])unlinkat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+unlinkat[\s]+|([\s]+|[,])unlinkat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit augenrules 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_unlinkat_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_unlinkat_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+unlinkat[\s]+|([\s]+|[,])unlinkat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+unlinkat[\s]+|([\s]+|[,])unlinkat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit file eacces  oval:ssg-test_32bit_arufm_eacces_unlinkat_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eacces_unlinkat_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+unlinkat[\s]+|([\s]+|[,])unlinkat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+unlinkat[\s]+|([\s]+|[,])unlinkat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 32-bit file eperm  oval:ssg-test_32bit_arufm_eperm_unlinkat_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_arufm_eperm_unlinkat_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+unlinkat[\s]+|([\s]+|[,])unlinkat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+unlinkat[\s]+|([\s]+|[,])unlinkat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit file eacces  oval:ssg-test_64bit_arufm_eacces_unlinkat_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eacces_unlinkat_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+unlinkat[\s]+|([\s]+|[,])unlinkat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+unlinkat[\s]+|([\s]+|[,])unlinkat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EACCES)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1

audit auditctl 64-bit file eperm  oval:ssg-test_64bit_arufm_eperm_unlinkat_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_arufm_eperm_unlinkat_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+unlinkat[\s]+|([\s]+|[,])unlinkat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+unlinkat[\s]+|([\s]+|[,])unlinkat([\s]+|[,])))(?:(?!-F[\s]+a\d&).)*(?:-F\s+exit=-EPERM)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$
/etc/audit/audit.rules1
Ensure auditd Collects Information on Kernel Module Unloading - delete_modulexccdf_org.ssgproject.content_rule_audit_rules_kernel_module_loading_delete medium

Ensure auditd Collects Information on Kernel Module Unloading - delete_module

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_kernel_module_loading_delete
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_kernel_module_loading_delete:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000130, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), AC-6(9), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.2.7, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000471-GPOS-00216, SRG-OS-000477-GPOS-00222, SRG-OS-000477-VMM-001970

Description
To capture kernel module unloading events, use following line, setting ARCH to either b32 for 32-bit system, or having two lines for both b32 and b64 in case your system is 64-bit:
-a always,exit -F arch=ARCH -S delete_module -F key=modules
Place to add the line depends on a way auditd daemon is configured. If it is configured to use the augenrules program (the default), add the line to a file with suffix .rules in the directory /etc/audit/rules.d. If the auditd daemon is configured to use the auditctl utility, add the line to file /etc/audit/audit.rules.
Rationale
The removal of kernel modules can be used to alter the behavior of the kernel and potentially introduce malicious code into kernel space. It is important to have an audit trail of modules that have been introduced into the kernel.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
# Note: 32-bit and 64-bit kernel syscall numbers not always line up =>
#       it's required on a 64-bit system to check also for the presence
#       of 32-bit's equivalent of the corresponding rule.
#       (See `man 7 audit.rules` for details )
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS=""
	SYSCALL="delete_module"
	KEY="modules"
	SYSCALL_GROUPING="delete_module"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,-a%20always%2Cexit%20-F%20arch%3Db32%20-S%20delete_module%20-k%20module-change%0A-a%20always%2Cexit%20-F%20arch%3Db64%20-S%20delete_module%20-k%20module-change%0A
        mode: 0600
        path: /etc/audit/rules.d/75-kernel-module-loading-delete.rules
        overwrite: true
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit delete_module  oval:ssg-test_32bit_ardm_delete_module_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_delete_module_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+delete_module[\s]+|([\s]+|[,])delete_module([\s]+|[,]))).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit delete_module  oval:ssg-test_64bit_ardm_delete_module_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_delete_module_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+delete_module[\s]+|([\s]+|[,])delete_module([\s]+|[,]))).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit delete_module  oval:ssg-test_32bit_ardm_delete_module_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_delete_module_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+delete_module[\s]+|([\s]+|[,])delete_module([\s]+|[,]))).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit delete_module  oval:ssg-test_64bit_ardm_delete_module_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_delete_module_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+delete_module[\s]+|([\s]+|[,])delete_module([\s]+|[,]))).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Ensure auditd Collects Information on Kernel Module Loading - init_modulexccdf_org.ssgproject.content_rule_audit_rules_kernel_module_loading_init medium

Ensure auditd Collects Information on Kernel Module Loading - init_module

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_kernel_module_loading_init
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_kernel_module_loading_init:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000130, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), AC-6(9), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.2.7, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000471-GPOS-00216, SRG-OS-000477-GPOS-00222, SRG-OS-000477-VMM-001970

Description
To capture kernel module loading events, use following line, setting ARCH to either b32 for 32-bit system, or having two lines for both b32 and b64 in case your system is 64-bit:
-a always,exit -F arch=ARCH -S init_module -F key=modules
Place to add the line depends on a way auditd daemon is configured. If it is configured to use the augenrules program (the default), add the line to a file with suffix .rules in the directory /etc/audit/rules.d. If the auditd daemon is configured to use the auditctl utility, add the line to file /etc/audit/audit.rules.
Rationale
The addition of kernel modules can be used to alter the behavior of the kernel and potentially introduce malicious code into kernel space. It is important to have an audit trail of modules that have been introduced into the kernel.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
# Note: 32-bit and 64-bit kernel syscall numbers not always line up =>
#       it's required on a 64-bit system to check also for the presence
#       of 32-bit's equivalent of the corresponding rule.
#       (See `man 7 audit.rules` for details )
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS=""
	SYSCALL="init_module"
	KEY="modules"
	SYSCALL_GROUPING="init_module finit_module"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,-a%20always%2Cexit%20-F%20arch%3Db32%20-S%20init_module%20-k%20module-change%0A-a%20always%2Cexit%20-F%20arch%3Db64%20-S%20init_module%20-k%20module-change%0A
        mode: 0600
        path: /etc/audit/rules.d/75-kernel-module-loading-init.rules
        overwrite: true
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules 32-bit init_module  oval:ssg-test_32bit_ardm_init_module_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_init_module_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+init_module[\s]+|([\s]+|[,])init_module([\s]+|[,]))).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit augenrules 64-bit init_module  oval:ssg-test_64bit_ardm_init_module_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_init_module_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+init_module[\s]+|([\s]+|[,])init_module([\s]+|[,]))).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl 32-bit init_module  oval:ssg-test_32bit_ardm_init_module_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_32bit_ardm_init_module_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b32[\s]+)(?:.*(-S[\s]+init_module[\s]+|([\s]+|[,])init_module([\s]+|[,]))).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

audit auditctl 64-bit init_module  oval:ssg-test_64bit_ardm_init_module_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_64bit_ardm_init_module_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+(?:.*-F[\s]+arch=b64[\s]+)(?:.*(-S[\s]+init_module[\s]+|([\s]+|[,])init_module([\s]+|[,]))).*(-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Ensure auditd Collects Information on the Use of Privileged Commands - atxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_at medium

Ensure auditd Collects Information on the Use of Privileged Commands - at

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_at
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_privileged_commands_at:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-000172, AU-2(d), AU-12(c), AC-6(9), CM-6(a), FAU_GEN.1.1.c, SRG-OS-000471-VMM-001910

Description
At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/bin/at -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/bin/at -F auid>=1000 -F auid!=unset -F key=privileged
Rationale
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/bin/at"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_at
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Perform remediation of Audit rules for /usr/bin/at
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/bin/at -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
      set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/at -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/at -F auid>=1000
          -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/bin/at -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|")
          }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/at -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/at -F auid>=1000
          -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_at
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules at  oval:ssg-test_audit_rules_privileged_commands_at_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_at_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/bin\/at[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl at  oval:ssg-test_audit_rules_privileged_commands_at_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_at_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/bin\/at[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Ensure auditd Collects Information on the Use of Privileged Commands - chagexccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_chage medium

Ensure auditd Collects Information on the Use of Privileged Commands - chage

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_chage
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_privileged_commands_chage:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000135, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2, CIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3, AC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a), DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000468-GPOS-00212, SRG-OS-000471-GPOS-00215, SRG-OS-000471-VMM-001910

Description
At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/bin/chage -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/bin/chage -F auid>=1000 -F auid!=unset -F key=privileged
Rationale
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/bin/chage"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_chage
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Perform remediation of Audit rules for /usr/bin/chage
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/bin/chage -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
      set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/chage -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/chage -F auid>=1000
          -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/bin/chage -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|")
          }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/chage -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/chage -F auid>=1000
          -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_chage
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules chage  oval:ssg-test_audit_rules_privileged_commands_chage_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_chage_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/bin\/chage[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl chage  oval:ssg-test_audit_rules_privileged_commands_chage_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_chage_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/bin\/chage[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Ensure auditd Collects Information on the Use of Privileged Commands - chshxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_chsh medium

Ensure auditd Collects Information on the Use of Privileged Commands - chsh

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_chsh
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_privileged_commands_chsh:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2, CIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3, AC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a), DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000471-VMM-001910

Description
At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/bin/chsh -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/bin/chsh -F auid>=1000 -F auid!=unset -F key=privileged
Rationale
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/bin/chsh"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_chsh
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Perform remediation of Audit rules for /usr/bin/chsh
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/bin/chsh -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
      set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/chsh -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/chsh -F auid>=1000
          -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/bin/chsh -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|")
          }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/chsh -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/chsh -F auid>=1000
          -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_chsh
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules chsh  oval:ssg-test_audit_rules_privileged_commands_chsh_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_chsh_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/bin\/chsh[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl chsh  oval:ssg-test_audit_rules_privileged_commands_chsh_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_chsh_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/bin\/chsh[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Ensure auditd Collects Information on the Use of Privileged Commands - crontabxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_crontab medium

Ensure auditd Collects Information on the Use of Privileged Commands - crontab

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_crontab
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_privileged_commands_crontab:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000135, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2, AU-2(d), AU-12(c), AC-6(9), CM-6(a), DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000471-VMM-001910

Description
At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/bin/crontab -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/bin/crontab -F auid>=1000 -F auid!=unset -F key=privileged
Rationale
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/bin/crontab"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_crontab
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Perform remediation of Audit rules for /usr/bin/crontab
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/bin/crontab -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
      set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/crontab -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/crontab -F
          auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/bin/crontab -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|")
          }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/crontab -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/crontab -F
          auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_crontab
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules crontab  oval:ssg-test_audit_rules_privileged_commands_crontab_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_crontab_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/bin\/crontab[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl crontab  oval:ssg-test_audit_rules_privileged_commands_crontab_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_crontab_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/bin\/crontab[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Ensure auditd Collects Information on the Use of Privileged Commands - gpasswdxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_gpasswd medium

Ensure auditd Collects Information on the Use of Privileged Commands - gpasswd

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_gpasswd
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_privileged_commands_gpasswd:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000135, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2, CIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3, AC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a), DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1, FAU_GEN.1.1.c, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000471-VMM-001910

Description
At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/bin/gpasswd -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/bin/gpasswd -F auid>=1000 -F auid!=unset -F key=privileged
Rationale
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/bin/gpasswd"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_gpasswd
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Perform remediation of Audit rules for /usr/bin/gpasswd
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/bin/gpasswd -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
      set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/gpasswd -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/gpasswd -F
          auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/bin/gpasswd -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|")
          }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/gpasswd -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/gpasswd -F
          auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_gpasswd
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules gpasswd  oval:ssg-test_audit_rules_privileged_commands_gpasswd_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_gpasswd_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/bin\/gpasswd[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl gpasswd  oval:ssg-test_audit_rules_privileged_commands_gpasswd_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_gpasswd_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/bin\/gpasswd[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Ensure auditd Collects Information on the Use of Privileged Commands - mountxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_mount medium

Ensure auditd Collects Information on the Use of Privileged Commands - mount

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_mount
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_privileged_commands_mount:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-000135, CCI-000172, CCI-002884, AU-2(d), AU-12(c), AC-6(9), CM-6(a), FAU_GEN.1.1.c, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000392-GPOS-00172, SRG-OS-000471-VMM-001910

Description
At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/bin/mount -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/bin/mount -F auid>=1000 -F auid!=unset -F key=privileged
Rationale
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/bin/mount"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_mount
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Perform remediation of Audit rules for /usr/bin/mount
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/bin/mount -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
      set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/mount -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/mount -F auid>=1000
          -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/bin/mount -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|")
          }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/mount -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/mount -F auid>=1000
          -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_mount
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules mount  oval:ssg-test_audit_rules_privileged_commands_mount_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_mount_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/bin\/mount[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl mount  oval:ssg-test_audit_rules_privileged_commands_mount_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_mount_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/bin\/mount[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Ensure auditd Collects Information on the Use of Privileged Commands - newgidmapxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_newgidmap medium

Ensure auditd Collects Information on the Use of Privileged Commands - newgidmap

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_newgidmap
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_privileged_commands_newgidmap:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-000172, CIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3, AC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a), FAU_GEN.1.1.c, SRG-OS-000471-VMM-001910

Description
At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/bin/newgidmap -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/bin/newgidmap -F auid>=1000 -F auid!=unset -F key=privileged
Rationale
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/bin/newgidmap"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_newgidmap
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Perform remediation of Audit rules for /usr/bin/newgidmap
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/bin/newgidmap -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
      set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/newgidmap -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/newgidmap
          -F auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/bin/newgidmap -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|")
          }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/newgidmap -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/newgidmap
          -F auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_newgidmap
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules newgidmap  oval:ssg-test_audit_rules_privileged_commands_newgidmap_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_newgidmap_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/bin\/newgidmap[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl newgidmap  oval:ssg-test_audit_rules_privileged_commands_newgidmap_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_newgidmap_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/bin\/newgidmap[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Ensure auditd Collects Information on the Use of Privileged Commands - newgrpxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_newgrp medium

Ensure auditd Collects Information on the Use of Privileged Commands - newgrp

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_newgrp
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_privileged_commands_newgrp:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000130, CCI-000169, CCI-000135, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2, CIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3, AC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a), DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1, FAU_GEN.1.1.c, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000471-VMM-001910

Description
At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/bin/newgrp -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/bin/newgrp -F auid>=1000 -F auid!=unset -F key=privileged
Rationale
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/bin/newgrp"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_newgrp
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Perform remediation of Audit rules for /usr/bin/newgrp
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/bin/newgrp -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
      set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/newgrp -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/newgrp -F
          auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/bin/newgrp -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|")
          }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/newgrp -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/newgrp -F
          auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_newgrp
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules newgrp  oval:ssg-test_audit_rules_privileged_commands_newgrp_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_newgrp_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/bin\/newgrp[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl newgrp  oval:ssg-test_audit_rules_privileged_commands_newgrp_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_newgrp_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/bin\/newgrp[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Ensure auditd Collects Information on the Use of Privileged Commands - newuidmapxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_newuidmap medium

Ensure auditd Collects Information on the Use of Privileged Commands - newuidmap

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_newuidmap
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_privileged_commands_newuidmap:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-000172, CIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3, AC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a), FAU_GEN.1.1.c, SRG-OS-000471-VMM-001910

Description
At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/bin/newuidmap -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/bin/newuidmap -F auid>=1000 -F auid!=unset -F key=privileged
Rationale
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/bin/newuidmap"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_newuidmap
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Perform remediation of Audit rules for /usr/bin/newuidmap
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/bin/newuidmap -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
      set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/newuidmap -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/newuidmap
          -F auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/bin/newuidmap -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|")
          }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/newuidmap -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/newuidmap
          -F auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_newuidmap
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules newuidmap  oval:ssg-test_audit_rules_privileged_commands_newuidmap_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_newuidmap_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/bin\/newuidmap[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl newuidmap  oval:ssg-test_audit_rules_privileged_commands_newuidmap_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_newuidmap_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/bin\/newuidmap[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Ensure auditd Collects Information on the Use of Privileged Commands - passwdxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_passwd medium

Ensure auditd Collects Information on the Use of Privileged Commands - passwd

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_passwd
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_privileged_commands_passwd:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000135, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2, CIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3, AC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a), DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1, FAU_GEN.1.1.c, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000471-VMM-001910

Description
At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/bin/passwd -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/bin/passwd -F auid>=1000 -F auid!=unset -F key=privileged
Rationale
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/bin/passwd"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_passwd
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Perform remediation of Audit rules for /usr/bin/passwd
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/bin/passwd -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
      set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/passwd -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/passwd -F
          auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/bin/passwd -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|")
          }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/passwd -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/passwd -F
          auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_passwd
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules passwd  oval:ssg-test_audit_rules_privileged_commands_passwd_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_passwd_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/bin\/passwd[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl passwd  oval:ssg-test_audit_rules_privileged_commands_passwd_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_passwd_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/bin\/passwd[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Ensure auditd Collects Information on the Use of Privileged Commands - pt_chownxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_pt_chown medium

Ensure auditd Collects Information on the Use of Privileged Commands - pt_chown

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_pt_chown
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_privileged_commands_pt_chown:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000135, CCI-000172, CCI-002884, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2, AU-2(d), AU-12(c), AC-6(9), CM-6(a), DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1, SRG-OS-000042-GPOS-00020, SRG-OS-000392-GPOS-00172, SRG-OS-000471-GPOS-00215, SRG-OS-000471-VMM-001910

Description
At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/libexec/pt_chown -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/libexec/pt_chown -F auid>=1000 -F auid!=unset -F key=privileged
Rationale
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/libexec/pt_chown"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_pt_chown
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Perform remediation of Audit rules for /usr/libexec/pt_chown
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/libexec/pt_chown -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
      set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/libexec/pt_chown -F
          auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/libexec/pt_chown
          -F auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/libexec/pt_chown -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|")
          }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/libexec/pt_chown -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/libexec/pt_chown
          -F auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_pt_chown
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules pt_chown  oval:ssg-test_audit_rules_privileged_commands_pt_chown_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_pt_chown_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/libexec\/pt_chown[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl pt_chown  oval:ssg-test_audit_rules_privileged_commands_pt_chown_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_pt_chown_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/libexec\/pt_chown[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Ensure auditd Collects Information on the Use of Privileged Commands - ssh-keysignxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_ssh_keysign medium

Ensure auditd Collects Information on the Use of Privileged Commands - ssh-keysign

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_ssh_keysign
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_privileged_commands_ssh_keysign:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000135, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2, AU-2(d), AU-12(c), AC-6(9), CM-6(a), DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1, FAU_GEN.1.1.c, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000471-VMM-001910

Description
At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/libexec/openssh/ssh-keysign -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/libexec/openssh/ssh-keysign -F auid>=1000 -F auid!=unset -F key=privileged
Rationale
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/libexec/openssh/ssh-keysign"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_ssh_keysign
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Perform remediation of Audit rules for /usr/libexec/openssh/ssh-keysign
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/libexec/openssh/ssh-keysign -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
      set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/libexec/openssh/ssh-keysign
          -F auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/libexec/openssh/ssh-keysign
          -F auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/libexec/openssh/ssh-keysign -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|")
          }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/libexec/openssh/ssh-keysign -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/libexec/openssh/ssh-keysign
          -F auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_ssh_keysign
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules ssh_keysign  oval:ssg-test_audit_rules_privileged_commands_ssh_keysign_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_ssh_keysign_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/libexec\/openssh\/ssh-keysign[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl ssh_keysign  oval:ssg-test_audit_rules_privileged_commands_ssh_keysign_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_ssh_keysign_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/libexec\/openssh\/ssh-keysign[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Ensure auditd Collects Information on the Use of Privileged Commands - suxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_su medium

Ensure auditd Collects Information on the Use of Privileged Commands - su

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_su
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_privileged_commands_su:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2, AU-2(d), AU-12(c), AC-6(9), CM-6(a), DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1, FAU_GEN.1.1.c, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000064-GPOS-0003, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000466-GPOS-00210, SRG-OS-000471-VMM-001910

Description
At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/bin/su -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/bin/su -F auid>=1000 -F auid!=unset -F key=privileged
Rationale
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/bin/su"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_su
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Perform remediation of Audit rules for /usr/bin/su
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/bin/su -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
      set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/su -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/su -F auid>=1000
          -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/bin/su -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|")
          }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/su -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/su -F auid>=1000
          -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_su
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules su  oval:ssg-test_audit_rules_privileged_commands_su_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_su_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/bin\/su[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl su  oval:ssg-test_audit_rules_privileged_commands_su_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_su_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/bin\/su[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Ensure auditd Collects Information on the Use of Privileged Commands - sudoxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_sudo medium

Ensure auditd Collects Information on the Use of Privileged Commands - sudo

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_sudo
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_privileged_commands_sudo:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  BP28(R19), 1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2, AU-2(d), AU-12(c), AC-6(9), CM-6(a), DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1, FAU_GEN.1.1.c, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000466-GPOS-00210, SRG-OS-000471-VMM-001910

Description
At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/bin/sudo -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/bin/sudo -F auid>=1000 -F auid!=unset -F key=privileged
Rationale
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/bin/sudo"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_sudo
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Perform remediation of Audit rules for /usr/bin/sudo
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/bin/sudo -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
      set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/sudo -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/sudo -F auid>=1000
          -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/bin/sudo -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|")
          }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/sudo -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/sudo -F auid>=1000
          -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_sudo
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules sudo  oval:ssg-test_audit_rules_privileged_commands_sudo_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_sudo_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/bin\/sudo[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl sudo  oval:ssg-test_audit_rules_privileged_commands_sudo_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_sudo_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/bin\/sudo[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Ensure auditd Collects Information on the Use of Privileged Commands - sudoeditxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_sudoedit medium

Ensure auditd Collects Information on the Use of Privileged Commands - sudoedit

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_sudoedit
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_privileged_commands_sudoedit:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2, AU-2(d), AU-12(c), AC-6(9), CM-6(a), DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1, FAU_GEN.1.1.c, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000471-VMM-001910

Description
At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/bin/sudoedit -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/bin/sudoedit -F auid>=1000 -F auid!=unset -F key=privileged
Rationale
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/bin/sudoedit"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_sudoedit
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Perform remediation of Audit rules for /usr/bin/sudoedit
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/bin/sudoedit -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
      set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/sudoedit -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/sudoedit -F
          auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/bin/sudoedit -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|")
          }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/sudoedit -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/sudoedit -F
          auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_sudoedit
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules sudoedit  oval:ssg-test_audit_rules_privileged_commands_sudoedit_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_sudoedit_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/bin\/sudoedit[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl sudoedit  oval:ssg-test_audit_rules_privileged_commands_sudoedit_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_sudoedit_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/bin\/sudoedit[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Ensure auditd Collects Information on the Use of Privileged Commands - umountxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_umount medium

Ensure auditd Collects Information on the Use of Privileged Commands - umount

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_umount
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_privileged_commands_umount:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000135, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2, AU-2(d), AU-12(c), AC-6(9), CM-6(a), DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000392-GPOS-00172, SRG-OS-000471-GPOS-00215, SRG-OS-000471-VMM-001910

Description
At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/bin/umount -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/bin/umount -F auid>=1000 -F auid!=unset -F key=privileged
Rationale
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/bin/umount"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_umount
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Perform remediation of Audit rules for /usr/bin/umount
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/bin/umount -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
      set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/umount -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/umount -F
          auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/bin/umount -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|")
          }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/umount -F auid>=1000 -F auid!=unset
          (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/umount -F
          auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_umount
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules umount  oval:ssg-test_audit_rules_privileged_commands_umount_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_umount_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/bin\/umount[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl umount  oval:ssg-test_audit_rules_privileged_commands_umount_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_umount_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/bin\/umount[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Ensure auditd Collects Information on the Use of Privileged Commands - unix_chkpwdxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_unix_chkpwd medium

Ensure auditd Collects Information on the Use of Privileged Commands - unix_chkpwd

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_unix_chkpwd
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_privileged_commands_unix_chkpwd:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2, CIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3, CIP-007-3 R6.5, AC-2(4), AU-2(d), AU-3, AU-3.1, AU-12(a), AU-12(c), AU-12.1(ii), AU-12.1(iv), AC-6(9), CM-6(a), MA-4(1)(a), DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1, FAU_GEN.1.1.c, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000471-VMM-001910

Description
At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/sbin/unix_chkpwd -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/sbin/unix_chkpwd -F auid>=1000 -F auid!=unset -F key=privileged
Rationale
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/sbin/unix_chkpwd"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(a)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-12.1(ii)
    - NIST-800-53-AU-12.1(iv)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-AU-3
    - NIST-800-53-AU-3.1
    - NIST-800-53-CM-6(a)
    - NIST-800-53-MA-4(1)(a)
    - audit_rules_privileged_commands_unix_chkpwd
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Perform remediation of Audit rules for /usr/sbin/unix_chkpwd
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/sbin/unix_chkpwd -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
      set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/sbin/unix_chkpwd -F
          auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/sbin/unix_chkpwd
          -F auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/sbin/unix_chkpwd -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|")
          }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/sbin/unix_chkpwd -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/sbin/unix_chkpwd
          -F auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(a)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-12.1(ii)
    - NIST-800-53-AU-12.1(iv)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-AU-3
    - NIST-800-53-AU-3.1
    - NIST-800-53-CM-6(a)
    - NIST-800-53-MA-4(1)(a)
    - audit_rules_privileged_commands_unix_chkpwd
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules unix_chkpwd  oval:ssg-test_audit_rules_privileged_commands_unix_chkpwd_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_unix_chkpwd_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/sbin\/unix_chkpwd[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl unix_chkpwd  oval:ssg-test_audit_rules_privileged_commands_unix_chkpwd_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_unix_chkpwd_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/sbin\/unix_chkpwd[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Ensure auditd Collects Information on the Use of Privileged Commands - userhelperxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_userhelper medium

Ensure auditd Collects Information on the Use of Privileged Commands - userhelper

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_userhelper
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_privileged_commands_userhelper:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000135, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2, AU-2(d), AU-12(c), AC-6(9), CM-6(a), DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1, FAU_GEN.1.1.c, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000471-VMM-001910

Description
At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/sbin/userhelper -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/sbin/userhelper -F auid>=1000 -F auid!=unset -F key=privileged
Rationale
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/sbin/userhelper"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_userhelper
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Perform remediation of Audit rules for /usr/sbin/userhelper
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/sbin/userhelper -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
      set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/sbin/userhelper -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/sbin/userhelper
          -F auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/sbin/userhelper -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|")
          }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/sbin/userhelper -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/sbin/userhelper
          -F auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_userhelper
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules userhelper  oval:ssg-test_audit_rules_privileged_commands_userhelper_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_userhelper_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/sbin\/userhelper[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl userhelper  oval:ssg-test_audit_rules_privileged_commands_userhelper_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_userhelper_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/sbin\/userhelper[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Ensure auditd Collects Information on the Use of Privileged Commands - usernetctlxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_usernetctl medium

Ensure auditd Collects Information on the Use of Privileged Commands - usernetctl

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_usernetctl
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_privileged_commands_usernetctl:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-000172, CIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3, AC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a), FAU_GEN.1.1.c, SRG-OS-000471-VMM-001910

Description
At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/sbin/usernetctl -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/sbin/usernetctl -F auid>=1000 -F auid!=unset -F key=privileged
Rationale
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/sbin/usernetctl"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_usernetctl
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Perform remediation of Audit rules for /usr/sbin/usernetctl
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/sbin/usernetctl -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
      set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/sbin/usernetctl -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/sbin/usernetctl
          -F auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F path=/usr/sbin/usernetctl -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|")
          }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/sbin/usernetctl -F auid>=1000 -F
          auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/sbin/usernetctl
          -F auid>=1000 -F auid!=unset -F key=privileged
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_privileged_commands_usernetctl
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules usernetctl  oval:ssg-test_audit_rules_privileged_commands_usernetctl_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_usernetctl_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/sbin\/usernetctl[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl usernetctl  oval:ssg-test_audit_rules_privileged_commands_usernetctl_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_privileged_commands_usernetctl_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^[\s]*-a[\s]+always,exit[\s]+-F[\s]+path=\/usr\/sbin\/usernetctl[\s]+-F[\s]+auid>=1000[\s]+-F[\s]+auid!=(?:4294967295|unset)[\s]+(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$1
Record Events that Modify User/Group Information via open syscall - /etc/groupxccdf_org.ssgproject.content_rule_audit_rules_etc_group_open medium

Record Events that Modify User/Group Information via open syscall - /etc/group

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_etc_group_open
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_etc_group_open:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3, AC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a), FAU_GEN.1.1.c

Description
The audit system should collect write events to /etc/group file for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S open -F a1&03 -F path=/etc/group -F auid>=1000 -F auid!=unset -F key=modify
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S open -F a1&03 -F path=/etc/group -F auid>=1000 -F auid!=unset -F key=modify
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S open -F a1&03 -F path=/etc/group -F auid>=1000 -F auid!=unset -F key=modify
Rationale
Creation of groups through direct edition of /etc/group could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S open -F a1&03 -F path=/etc/group -F auid>=1000 -F auid!=unset -F key=modify

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F a1&03 -F path=/etc/group"
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="open"
	KEY="user-modify"
	SYSCALL_GROUPING=""
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_group_open
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit open tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_group_open
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for open for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open
        syscall_grouping: []

    - name: Check existence of open in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a1&03 -F path=/etc/group -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/modify.rules
      set_fact: audit_file="/etc/audit/rules.d/modify.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a1&03 -F path=/etc/group -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F a1&03 -F
          path=/etc/group -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open
        syscall_grouping: []

    - name: Check existence of open in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a1&03 -F path=/etc/group -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a1&03 -F path=/etc/group -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F a1&03 -F
          path=/etc/group -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_group_open
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for open for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open
        syscall_grouping: []

    - name: Check existence of open in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a1&03 -F path=/etc/group -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/modify.rules
      set_fact: audit_file="/etc/audit/rules.d/modify.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a1&03 -F path=/etc/group -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F a1&03 -F
          path=/etc/group -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open
        syscall_grouping: []

    - name: Check existence of open in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a1&03 -F path=/etc/group -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a1&03 -F path=/etc/group -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F a1&03 -F
          path=/etc/group -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_group_open
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

defined audit rule must exist  oval:ssg-test_audit_rules_tc_group_open_32bit_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_group_open_32bit_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F[\s]+a1&03)[\s]+(?:-F[\s]+path=/etc/group)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_audit_rules_tc_group_open_64bit_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_group_open_64bit_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F[\s]+a1&03)[\s]+(?:-F[\s]+path=/etc/group)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

defined audit rule must exist  oval:ssg-test_audit_rules_tc_group_open_32bit_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_group_open_32bit_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F[\s]+a1&03)[\s]+(?:-F[\s]+path=/etc/group)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_audit_rules_tc_group_open_64bit_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_group_open_64bit_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F[\s]+a1&03)[\s]+(?:-F[\s]+path=/etc/group)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$/etc/audit/audit.rules1
Record Events that Modify User/Group Information via open_by_handle_at syscall - /etc/groupxccdf_org.ssgproject.content_rule_audit_rules_etc_group_open_by_handle_at medium

Record Events that Modify User/Group Information via open_by_handle_at syscall - /etc/group

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_etc_group_open_by_handle_at
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_etc_group_open_by_handle_at:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3, AC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a), FAU_GEN.1.1.c

Description
The audit system should collect write events to /etc/group file for all group and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S open_by_handle_at -F a2&03 -F path=/etc/group -F auid>=1000 -F auid!=unset -F key=modify
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S open_by_handle_at -F a2&03 -F path=/etc/group -F auid>=1000 -F auid!=unset -F key=modify
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S open_by_handle_at -F a2&03 -F path=/etc/group -F auid>=1000 -F auid!=unset -F key=modify
Rationale
Creation of groups through direct edition of /etc/group could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&03 -F path=/etc/group -F auid>=1000 -F auid!=unset -F key=modify

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F a2&03 -F path=/etc/group"
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="open_by_handle_at"
	KEY="user-modify"
	SYSCALL_GROUPING=""
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_group_open_by_handle_at
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit open_by_handle_at tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_group_open_by_handle_at
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for open_by_handle_at for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open_by_handle_at
        syscall_grouping: []

    - name: Check existence of open_by_handle_at in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a2&03 -F path=/etc/group -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/modify.rules
      set_fact: audit_file="/etc/audit/rules.d/modify.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a2&03 -F path=/etc/group -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F a2&03 -F
          path=/etc/group -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open_by_handle_at
        syscall_grouping: []

    - name: Check existence of open_by_handle_at in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a2&03 -F path=/etc/group -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a2&03 -F path=/etc/group -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F a2&03 -F
          path=/etc/group -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_group_open_by_handle_at
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for open_by_handle_at for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open_by_handle_at
        syscall_grouping: []

    - name: Check existence of open_by_handle_at in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a2&03 -F path=/etc/group -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/modify.rules
      set_fact: audit_file="/etc/audit/rules.d/modify.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a2&03 -F path=/etc/group -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F a2&03 -F
          path=/etc/group -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open_by_handle_at
        syscall_grouping: []

    - name: Check existence of open_by_handle_at in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a2&03 -F path=/etc/group -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a2&03 -F path=/etc/group -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F a2&03 -F
          path=/etc/group -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_group_open_by_handle_at
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

defined audit rule must exist  oval:ssg-test_audit_rules_tc_group_open_by_handle_at_32bit_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_group_open_by_handle_at_32bit_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F[\s]+a2&03)[\s]+(?:-F[\s]+path=/etc/group)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_audit_rules_tc_group_open_by_handle_at_64bit_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_group_open_by_handle_at_64bit_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F[\s]+a2&03)[\s]+(?:-F[\s]+path=/etc/group)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

defined audit rule must exist  oval:ssg-test_audit_rules_tc_group_open_by_handle_at_32bit_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_group_open_by_handle_at_32bit_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F[\s]+a2&03)[\s]+(?:-F[\s]+path=/etc/group)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_audit_rules_tc_group_open_by_handle_at_64bit_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_group_open_by_handle_at_64bit_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F[\s]+a2&03)[\s]+(?:-F[\s]+path=/etc/group)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$/etc/audit/audit.rules1
Record Events that Modify User/Group Information via openat syscall - /etc/groupxccdf_org.ssgproject.content_rule_audit_rules_etc_group_openat medium

Record Events that Modify User/Group Information via openat syscall - /etc/group

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_etc_group_openat
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_etc_group_openat:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3, AC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a), FAU_GEN.1.1.c

Description
The audit system should collect write events to /etc/group file for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S openat -F a2&03 -F path=/etc/group -F auid>=1000 -F auid!=unset -F key=modify
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S openat -F a2&03 -F path=/etc/group -F auid>=1000 -F auid!=unset -F key=modify
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S openat -F a2&03 -F path=/etc/group -F auid>=1000 -F auid!=unset -F key=modify
Rationale
Creation of groups through direct edition of /etc/group could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&03 -F path=/etc/group -F auid>=1000 -F auid!=unset -F key=modify

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F a2&03 -F path=/etc/group"
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="openat"
	KEY="user-modify"
	SYSCALL_GROUPING=""
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_group_openat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit openat tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_group_openat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for openat for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - openat
        syscall_grouping: []

    - name: Check existence of openat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a2&03 -F path=/etc/group -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/modify.rules
      set_fact: audit_file="/etc/audit/rules.d/modify.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a2&03 -F path=/etc/group -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F a2&03 -F
          path=/etc/group -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - openat
        syscall_grouping: []

    - name: Check existence of openat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a2&03 -F path=/etc/group -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a2&03 -F path=/etc/group -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F a2&03 -F
          path=/etc/group -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_group_openat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for openat for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - openat
        syscall_grouping: []

    - name: Check existence of openat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a2&03 -F path=/etc/group -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/modify.rules
      set_fact: audit_file="/etc/audit/rules.d/modify.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a2&03 -F path=/etc/group -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F a2&03 -F
          path=/etc/group -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - openat
        syscall_grouping: []

    - name: Check existence of openat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a2&03 -F path=/etc/group -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a2&03 -F path=/etc/group -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F a2&03 -F
          path=/etc/group -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_group_openat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

defined audit rule must exist  oval:ssg-test_audit_rules_tc_group_openat_32bit_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_group_openat_32bit_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F[\s]+a2&03)[\s]+(?:-F[\s]+path=/etc/group)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_audit_rules_tc_group_openat_64bit_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_group_openat_64bit_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F[\s]+a2&03)[\s]+(?:-F[\s]+path=/etc/group)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

defined audit rule must exist  oval:ssg-test_audit_rules_tc_group_openat_32bit_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_group_openat_32bit_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F[\s]+a2&03)[\s]+(?:-F[\s]+path=/etc/group)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_audit_rules_tc_group_openat_64bit_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_group_openat_64bit_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F[\s]+a2&03)[\s]+(?:-F[\s]+path=/etc/group)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$/etc/audit/audit.rules1
Record Events that Modify User/Group Information via open syscall - /etc/gshadowxccdf_org.ssgproject.content_rule_audit_rules_etc_gshadow_open medium

Record Events that Modify User/Group Information via open syscall - /etc/gshadow

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_etc_gshadow_open
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_etc_gshadow_open:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3, AC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a), FAU_GEN.1.1.c

Description
The audit system should collect write events to /etc/gshadow file for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S open -F a1&03 -F path=/etc/gshadow -F auid>=1000 -F auid!=unset -F key=user-modify
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S open -F a1&03 -F path=/etc/gshadow -F auid>=1000 -F auid!=unset -F key=user-modify
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S open -F a1&03 -F path=/etc/gshadow -F auid>=1000 -F auid!=unset -F key=user-modify
Rationale
Creation of users through direct edition of /etc/gshadow could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S open -F a1&03 -F path=/etc/gshadow -F auid>=1000 -F auid!=unset -F key=user-modify

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F a1&03 -F path=/etc/gshadow"
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="open"
	KEY="user-modify"
	SYSCALL_GROUPING=""
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_gshadow_open
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit open tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_gshadow_open
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for open for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open
        syscall_grouping: []

    - name: Check existence of open in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a1&03 -F path=/etc/gshadow -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/modify.rules
      set_fact: audit_file="/etc/audit/rules.d/modify.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a1&03 -F path=/etc/gshadow -F
          auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F a1&03 -F
          path=/etc/gshadow -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open
        syscall_grouping: []

    - name: Check existence of open in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a1&03 -F path=/etc/gshadow -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a1&03 -F path=/etc/gshadow -F
          auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F a1&03 -F
          path=/etc/gshadow -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_gshadow_open
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for open for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open
        syscall_grouping: []

    - name: Check existence of open in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a1&03 -F path=/etc/gshadow -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/modify.rules
      set_fact: audit_file="/etc/audit/rules.d/modify.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a1&03 -F path=/etc/gshadow -F
          auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F a1&03 -F
          path=/etc/gshadow -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open
        syscall_grouping: []

    - name: Check existence of open in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a1&03 -F path=/etc/gshadow -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a1&03 -F path=/etc/gshadow -F
          auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F a1&03 -F
          path=/etc/gshadow -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_gshadow_open
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

defined audit rule must exist  oval:ssg-test_audit_rules_tc_gshadow_open_32bit_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_gshadow_open_32bit_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F[\s]+a1&03)[\s]+(?:-F[\s]+path=/etc/gshadow)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_audit_rules_tc_gshadow_open_64bit_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_gshadow_open_64bit_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F[\s]+a1&03)[\s]+(?:-F[\s]+path=/etc/gshadow)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

defined audit rule must exist  oval:ssg-test_audit_rules_tc_gshadow_open_32bit_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_gshadow_open_32bit_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F[\s]+a1&03)[\s]+(?:-F[\s]+path=/etc/gshadow)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_audit_rules_tc_gshadow_open_64bit_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_gshadow_open_64bit_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F[\s]+a1&03)[\s]+(?:-F[\s]+path=/etc/gshadow)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$/etc/audit/audit.rules1
Record Events that Modify User/Group Information via open_by_handle_at syscall - /etc/gshadowxccdf_org.ssgproject.content_rule_audit_rules_etc_gshadow_open_by_handle_at medium

Record Events that Modify User/Group Information via open_by_handle_at syscall - /etc/gshadow

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_etc_gshadow_open_by_handle_at
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_etc_gshadow_open_by_handle_at:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3, AC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a), FAU_GEN.1.1.c

Description
The audit system should collect write events to /etc/gshadow file for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S open_by_handle_at -F a2&03 -F path=/etc/gshadow -F auid>=1000 -F auid!=unset -F key=user-modify
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S open_by_handle_at -F a2&03 -F path=/etc/gshadow -F auid>=1000 -F auid!=unset -F key=user-modify
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S open_by_handle_at -F a2&03 -F path=/etc/gshadow -F auid>=1000 -F auid!=unset -F key=user-modify
Rationale
Creation of users through direct edition of /etc/gshadow could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&03 -F path=/etc/gshadow -F auid>=1000 -F auid!=unset -F key=user-modify

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F a2&03 -F path=/etc/gshadow"
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="open_by_handle_at"
	KEY="user-modify"
	SYSCALL_GROUPING=""
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_gshadow_open_by_handle_at
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit open_by_handle_at tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_gshadow_open_by_handle_at
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for open_by_handle_at for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open_by_handle_at
        syscall_grouping: []

    - name: Check existence of open_by_handle_at in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a2&03 -F path=/etc/gshadow -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/modify.rules
      set_fact: audit_file="/etc/audit/rules.d/modify.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a2&03 -F path=/etc/gshadow -F
          auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F a2&03 -F
          path=/etc/gshadow -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open_by_handle_at
        syscall_grouping: []

    - name: Check existence of open_by_handle_at in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a2&03 -F path=/etc/gshadow -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a2&03 -F path=/etc/gshadow -F
          auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F a2&03 -F
          path=/etc/gshadow -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_gshadow_open_by_handle_at
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for open_by_handle_at for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open_by_handle_at
        syscall_grouping: []

    - name: Check existence of open_by_handle_at in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a2&03 -F path=/etc/gshadow -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/modify.rules
      set_fact: audit_file="/etc/audit/rules.d/modify.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a2&03 -F path=/etc/gshadow -F
          auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F a2&03 -F
          path=/etc/gshadow -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open_by_handle_at
        syscall_grouping: []

    - name: Check existence of open_by_handle_at in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a2&03 -F path=/etc/gshadow -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a2&03 -F path=/etc/gshadow -F
          auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F a2&03 -F
          path=/etc/gshadow -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_gshadow_open_by_handle_at
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

defined audit rule must exist  oval:ssg-test_audit_rules_tc_gshadow_open_by_handle_at_32bit_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_gshadow_open_by_handle_at_32bit_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F[\s]+a2&03)[\s]+(?:-F[\s]+path=/etc/gshadow)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_audit_rules_tc_gshadow_open_by_handle_at_64bit_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_gshadow_open_by_handle_at_64bit_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F[\s]+a2&03)[\s]+(?:-F[\s]+path=/etc/gshadow)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

defined audit rule must exist  oval:ssg-test_audit_rules_tc_gshadow_open_by_handle_at_32bit_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_gshadow_open_by_handle_at_32bit_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F[\s]+a2&03)[\s]+(?:-F[\s]+path=/etc/gshadow)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_audit_rules_tc_gshadow_open_by_handle_at_64bit_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_gshadow_open_by_handle_at_64bit_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F[\s]+a2&03)[\s]+(?:-F[\s]+path=/etc/gshadow)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$/etc/audit/audit.rules1
Record Events that Modify User/Group Information via openat syscall - /etc/gshadowxccdf_org.ssgproject.content_rule_audit_rules_etc_gshadow_openat medium

Record Events that Modify User/Group Information via openat syscall - /etc/gshadow

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_etc_gshadow_openat
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_etc_gshadow_openat:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3, AC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a), FAU_GEN.1.1.c

Description
The audit system should collect write events to /etc/gshadow file for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S openat -F a2&03 -F path=/etc/gshadow -F auid>=1000 -F auid!=unset -F key=user-modify
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S openat -F a2&03 -F path=/etc/gshadow -F auid>=1000 -F auid!=unset -F key=user-modify
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S openat -F a2&03 -F path=/etc/gshadow -F auid>=1000 -F auid!=unset -F key=user-modify
Rationale
Creation of users through direct edition of /etc/gshadow could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&03 -F path=/etc/gshadow -F auid>=1000 -F auid!=unset -F key=user-modify

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F a2&03 -F path=/etc/gshadow"
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="openat"
	KEY="user-modify"
	SYSCALL_GROUPING=""
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_gshadow_openat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit openat tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_gshadow_openat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for openat for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - openat
        syscall_grouping: []

    - name: Check existence of openat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a2&03 -F path=/etc/gshadow -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/modify.rules
      set_fact: audit_file="/etc/audit/rules.d/modify.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a2&03 -F path=/etc/gshadow -F
          auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F a2&03 -F
          path=/etc/gshadow -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - openat
        syscall_grouping: []

    - name: Check existence of openat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a2&03 -F path=/etc/gshadow -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a2&03 -F path=/etc/gshadow -F
          auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F a2&03 -F
          path=/etc/gshadow -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_gshadow_openat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for openat for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - openat
        syscall_grouping: []

    - name: Check existence of openat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a2&03 -F path=/etc/gshadow -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/modify.rules
      set_fact: audit_file="/etc/audit/rules.d/modify.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a2&03 -F path=/etc/gshadow -F
          auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F a2&03 -F
          path=/etc/gshadow -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - openat
        syscall_grouping: []

    - name: Check existence of openat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a2&03 -F path=/etc/gshadow -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a2&03 -F path=/etc/gshadow -F
          auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F a2&03 -F
          path=/etc/gshadow -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_gshadow_openat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

defined audit rule must exist  oval:ssg-test_audit_rules_tc_gshadow_openat_32bit_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_gshadow_openat_32bit_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F[\s]+a2&03)[\s]+(?:-F[\s]+path=/etc/gshadow)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_audit_rules_tc_gshadow_openat_64bit_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_gshadow_openat_64bit_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F[\s]+a2&03)[\s]+(?:-F[\s]+path=/etc/gshadow)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

defined audit rule must exist  oval:ssg-test_audit_rules_tc_gshadow_openat_32bit_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_gshadow_openat_32bit_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F[\s]+a2&03)[\s]+(?:-F[\s]+path=/etc/gshadow)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_audit_rules_tc_gshadow_openat_64bit_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_gshadow_openat_64bit_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F[\s]+a2&03)[\s]+(?:-F[\s]+path=/etc/gshadow)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$/etc/audit/audit.rules1
Record Events that Modify User/Group Information via open syscall - /etc/passwdxccdf_org.ssgproject.content_rule_audit_rules_etc_passwd_open medium

Record Events that Modify User/Group Information via open syscall - /etc/passwd

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_etc_passwd_open
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_etc_passwd_open:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3, AC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a), FAU_GEN.1.1.c

Description
The audit system should collect write events to /etc/passwd file for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S open -F a1&03 -F path=/etc/passwd -F auid>=1000 -F auid!=unset -F key=modify
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S open -F a1&03 -F path=/etc/passwd -F auid>=1000 -F auid!=unset -F key=modify
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S open -F a1&03 -F path=/etc/passwd -F auid>=1000 -F auid!=unset -F key=modify
Rationale
Creation of users through direct edition of /etc/passwd could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S open -F a1&03 -F path=/etc/passwd -F auid>=1000 -F auid!=unset -F key=modify

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F a1&03 -F path=/etc/passwd"
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="open"
	KEY="user-modify"
	SYSCALL_GROUPING=""
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_passwd_open
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit open tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_passwd_open
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for open for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open
        syscall_grouping: []

    - name: Check existence of open in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a1&03 -F path=/etc/passwd -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/modify.rules
      set_fact: audit_file="/etc/audit/rules.d/modify.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a1&03 -F path=/etc/passwd -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F a1&03 -F
          path=/etc/passwd -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open
        syscall_grouping: []

    - name: Check existence of open in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a1&03 -F path=/etc/passwd -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a1&03 -F path=/etc/passwd -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F a1&03 -F
          path=/etc/passwd -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_passwd_open
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for open for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open
        syscall_grouping: []

    - name: Check existence of open in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a1&03 -F path=/etc/passwd -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/modify.rules
      set_fact: audit_file="/etc/audit/rules.d/modify.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a1&03 -F path=/etc/passwd -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F a1&03 -F
          path=/etc/passwd -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open
        syscall_grouping: []

    - name: Check existence of open in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a1&03 -F path=/etc/passwd -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a1&03 -F path=/etc/passwd -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F a1&03 -F
          path=/etc/passwd -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_passwd_open
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

defined audit rule must exist  oval:ssg-test_audit_rules_tc_passwd_open_32bit_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_passwd_open_32bit_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F[\s]+a1&03)[\s]+(?:-F[\s]+path=/etc/passwd)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_audit_rules_tc_passwd_open_64bit_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_passwd_open_64bit_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F[\s]+a1&03)[\s]+(?:-F[\s]+path=/etc/passwd)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

defined audit rule must exist  oval:ssg-test_audit_rules_tc_passwd_open_32bit_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_passwd_open_32bit_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F[\s]+a1&03)[\s]+(?:-F[\s]+path=/etc/passwd)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_audit_rules_tc_passwd_open_64bit_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_passwd_open_64bit_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F[\s]+a1&03)[\s]+(?:-F[\s]+path=/etc/passwd)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$/etc/audit/audit.rules1
Record Events that Modify User/Group Information via open_by_handle_at syscall - /etc/passwdxccdf_org.ssgproject.content_rule_audit_rules_etc_passwd_open_by_handle_at medium

Record Events that Modify User/Group Information via open_by_handle_at syscall - /etc/passwd

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_etc_passwd_open_by_handle_at
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_etc_passwd_open_by_handle_at:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3, AC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a), FAU_GEN.1.1.c

Description
The audit system should collect write events to /etc/passwd file for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S open_by_handle_at -F a2&03 -F path=/etc/passwd -F auid>=1000 -F auid!=unset -F key=modify
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S open_by_handle_at -F a2&03 -F path=/etc/passwd -F auid>=1000 -F auid!=unset -F key=modify
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S open_by_handle_at -F a2&03 -F path=/etc/passwd -F auid>=1000 -F auid!=unset -F key=modify
Rationale
Creation of users through direct edition of /etc/passwd could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&03 -F path=/etc/passwd -F auid>=1000 -F auid!=unset -F key=modify

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F a2&03 -F path=/etc/passwd"
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="open_by_handle_at"
	KEY="user-modify"
	SYSCALL_GROUPING=""
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_passwd_open_by_handle_at
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit open_by_handle_at tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_passwd_open_by_handle_at
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for open_by_handle_at for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open_by_handle_at
        syscall_grouping: []

    - name: Check existence of open_by_handle_at in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a2&03 -F path=/etc/passwd -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/modify.rules
      set_fact: audit_file="/etc/audit/rules.d/modify.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a2&03 -F path=/etc/passwd -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F a2&03 -F
          path=/etc/passwd -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open_by_handle_at
        syscall_grouping: []

    - name: Check existence of open_by_handle_at in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a2&03 -F path=/etc/passwd -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a2&03 -F path=/etc/passwd -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F a2&03 -F
          path=/etc/passwd -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_passwd_open_by_handle_at
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for open_by_handle_at for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open_by_handle_at
        syscall_grouping: []

    - name: Check existence of open_by_handle_at in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a2&03 -F path=/etc/passwd -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/modify.rules
      set_fact: audit_file="/etc/audit/rules.d/modify.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a2&03 -F path=/etc/passwd -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F a2&03 -F
          path=/etc/passwd -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open_by_handle_at
        syscall_grouping: []

    - name: Check existence of open_by_handle_at in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a2&03 -F path=/etc/passwd -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a2&03 -F path=/etc/passwd -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F a2&03 -F
          path=/etc/passwd -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_passwd_open_by_handle_at
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

defined audit rule must exist  oval:ssg-test_audit_rules_tc_passwd_open_by_handle_at_32bit_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_passwd_open_by_handle_at_32bit_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F[\s]+a2&03)[\s]+(?:-F[\s]+path=/etc/passwd)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_audit_rules_tc_passwd_open_by_handle_at_64bit_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_passwd_open_by_handle_at_64bit_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F[\s]+a2&03)[\s]+(?:-F[\s]+path=/etc/passwd)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

defined audit rule must exist  oval:ssg-test_audit_rules_tc_passwd_open_by_handle_at_32bit_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_passwd_open_by_handle_at_32bit_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F[\s]+a2&03)[\s]+(?:-F[\s]+path=/etc/passwd)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_audit_rules_tc_passwd_open_by_handle_at_64bit_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_passwd_open_by_handle_at_64bit_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F[\s]+a2&03)[\s]+(?:-F[\s]+path=/etc/passwd)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$/etc/audit/audit.rules1
Record Events that Modify User/Group Information via openat syscall - /etc/passwdxccdf_org.ssgproject.content_rule_audit_rules_etc_passwd_openat medium

Record Events that Modify User/Group Information via openat syscall - /etc/passwd

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_etc_passwd_openat
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_etc_passwd_openat:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3, AC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a), FAU_GEN.1.1.c

Description
The audit system should collect write events to /etc/passwd file for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S openat -F a2&03 -F path=/etc/passwd -F auid>=1000 -F auid!=unset -F key=modify
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S openat -F a2&03 -F path=/etc/passwd -F auid>=1000 -F auid!=unset -F key=modify
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S openat -F a2&03 -F path=/etc/passwd -F auid>=1000 -F auid!=unset -F key=modify
Rationale
Creation of users through direct edition of /etc/passwd could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S openat,open_by_handle_at -F a2&03 -F path=/etc/passwd -F auid>=1000 -F auid!=unset -F key=modify

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F a2&03 -F path=/etc/passwd"
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="openat"
	KEY="user-modify"
	SYSCALL_GROUPING=""
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_passwd_openat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit openat tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_passwd_openat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for openat for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - openat
        syscall_grouping: []

    - name: Check existence of openat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a2&03 -F path=/etc/passwd -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/modify.rules
      set_fact: audit_file="/etc/audit/rules.d/modify.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a2&03 -F path=/etc/passwd -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F a2&03 -F
          path=/etc/passwd -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - openat
        syscall_grouping: []

    - name: Check existence of openat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a2&03 -F path=/etc/passwd -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a2&03 -F path=/etc/passwd -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F a2&03 -F
          path=/etc/passwd -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_passwd_openat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for openat for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - openat
        syscall_grouping: []

    - name: Check existence of openat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a2&03 -F path=/etc/passwd -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/modify.rules
      set_fact: audit_file="/etc/audit/rules.d/modify.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a2&03 -F path=/etc/passwd -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F a2&03 -F
          path=/etc/passwd -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - openat
        syscall_grouping: []

    - name: Check existence of openat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a2&03 -F path=/etc/passwd -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a2&03 -F path=/etc/passwd -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F a2&03 -F
          path=/etc/passwd -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_passwd_openat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

defined audit rule must exist  oval:ssg-test_audit_rules_tc_passwd_openat_32bit_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_passwd_openat_32bit_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F[\s]+a2&03)[\s]+(?:-F[\s]+path=/etc/passwd)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_audit_rules_tc_passwd_openat_64bit_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_passwd_openat_64bit_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F[\s]+a2&03)[\s]+(?:-F[\s]+path=/etc/passwd)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

defined audit rule must exist  oval:ssg-test_audit_rules_tc_passwd_openat_32bit_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_passwd_openat_32bit_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F[\s]+a2&03)[\s]+(?:-F[\s]+path=/etc/passwd)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_audit_rules_tc_passwd_openat_64bit_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_passwd_openat_64bit_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F[\s]+a2&03)[\s]+(?:-F[\s]+path=/etc/passwd)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$/etc/audit/audit.rules1
Record Events that Modify User/Group Information via open syscall - /etc/shadowxccdf_org.ssgproject.content_rule_audit_rules_etc_shadow_open medium

Record Events that Modify User/Group Information via open syscall - /etc/shadow

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_etc_shadow_open
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_etc_shadow_open:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3, AC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a), FAU_GEN.1.1.c

Description
The audit system should collect write events to /etc/shadow file for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S open -F a1&03 -F path=/etc/shadow -F auid>=1000 -F auid!=unset -F key=user-modify
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S open -F a1&03 -F path=/etc/shadow -F auid>=1000 -F auid!=unset -F key=user-modify
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S open -F a1&03 -F path=/etc/shadow -F auid>=1000 -F auid!=unset -F key=user-modify
Rationale
Creation of users through direct edition of /etc/shadow could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S open,openat,open_by_handle_at -F a1&03 -F path=/etc/shadow -F auid>=1000 -F auid!=unset -F key=user-modify

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F a1&03 -F path=/etc/shadow"
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="open"
	KEY="user-modify"
	SYSCALL_GROUPING=""
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_shadow_open
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit open tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_shadow_open
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for open for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open
        syscall_grouping: []

    - name: Check existence of open in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a1&03 -F path=/etc/shadow -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/modify.rules
      set_fact: audit_file="/etc/audit/rules.d/modify.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a1&03 -F path=/etc/shadow -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F a1&03 -F
          path=/etc/shadow -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open
        syscall_grouping: []

    - name: Check existence of open in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a1&03 -F path=/etc/shadow -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a1&03 -F path=/etc/shadow -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F a1&03 -F
          path=/etc/shadow -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_shadow_open
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for open for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open
        syscall_grouping: []

    - name: Check existence of open in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a1&03 -F path=/etc/shadow -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/modify.rules
      set_fact: audit_file="/etc/audit/rules.d/modify.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a1&03 -F path=/etc/shadow -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F a1&03 -F
          path=/etc/shadow -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open
        syscall_grouping: []

    - name: Check existence of open in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a1&03 -F path=/etc/shadow -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a1&03 -F path=/etc/shadow -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F a1&03 -F
          path=/etc/shadow -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_shadow_open
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

defined audit rule must exist  oval:ssg-test_audit_rules_tc_shadow_open_32bit_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_shadow_open_32bit_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F[\s]+a1&03)[\s]+(?:-F[\s]+path=/etc/shadow)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_audit_rules_tc_shadow_open_64bit_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_shadow_open_64bit_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F[\s]+a1&03)[\s]+(?:-F[\s]+path=/etc/shadow)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

defined audit rule must exist  oval:ssg-test_audit_rules_tc_shadow_open_32bit_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_shadow_open_32bit_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F[\s]+a1&03)[\s]+(?:-F[\s]+path=/etc/shadow)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_audit_rules_tc_shadow_open_64bit_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_shadow_open_64bit_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open)(?:,[\S]+)*)[\s]+(?:-F[\s]+a1&03)[\s]+(?:-F[\s]+path=/etc/shadow)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$/etc/audit/audit.rules1
Record Events that Modify User/Group Information via open_by_handle_at syscall - /etc/shadowxccdf_org.ssgproject.content_rule_audit_rules_etc_shadow_open_by_handle_at medium

Record Events that Modify User/Group Information via open_by_handle_at syscall - /etc/shadow

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_etc_shadow_open_by_handle_at
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_etc_shadow_open_by_handle_at:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3, AC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a), FAU_GEN.1.1.c

Description
The audit system should collect write events to /etc/shadow file for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S open_by_handle_at -F a2&03 -F path=/etc/shadow -F auid>=1000 -F auid!=unset -F key=user-modify
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S open_by_handle_at -F a2&03 -F path=/etc/shadow -F auid>=1000 -F auid!=unset -F key=user-modify
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S open_by_handle_at -F a2&03 -F path=/etc/shadow -F auid>=1000 -F auid!=unset -F key=user-modify
Rationale
Creation of users through direct edition of /etc/shadow could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S open,openat,open_by_handle_at -F a2&03 -F path=/etc/shadow -F auid>=1000 -F auid!=unset -F key=user-modify

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F a2&03 -F path=/etc/shadow"
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="open_by_handle_at"
	KEY="user-modify"
	SYSCALL_GROUPING=""
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_shadow_open_by_handle_at
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit open_by_handle_at tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_shadow_open_by_handle_at
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for open_by_handle_at for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open_by_handle_at
        syscall_grouping: []

    - name: Check existence of open_by_handle_at in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a2&03 -F path=/etc/shadow -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/modify.rules
      set_fact: audit_file="/etc/audit/rules.d/modify.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a2&03 -F path=/etc/shadow -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F a2&03 -F
          path=/etc/shadow -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open_by_handle_at
        syscall_grouping: []

    - name: Check existence of open_by_handle_at in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a2&03 -F path=/etc/shadow -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a2&03 -F path=/etc/shadow -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F a2&03 -F
          path=/etc/shadow -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_shadow_open_by_handle_at
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for open_by_handle_at for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open_by_handle_at
        syscall_grouping: []

    - name: Check existence of open_by_handle_at in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a2&03 -F path=/etc/shadow -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/modify.rules
      set_fact: audit_file="/etc/audit/rules.d/modify.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a2&03 -F path=/etc/shadow -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F a2&03 -F
          path=/etc/shadow -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - open_by_handle_at
        syscall_grouping: []

    - name: Check existence of open_by_handle_at in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a2&03 -F path=/etc/shadow -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a2&03 -F path=/etc/shadow -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F a2&03 -F
          path=/etc/shadow -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_shadow_open_by_handle_at
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

defined audit rule must exist  oval:ssg-test_audit_rules_tc_shadow_open_by_handle_at_32bit_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_shadow_open_by_handle_at_32bit_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F[\s]+a2&03)[\s]+(?:-F[\s]+path=/etc/shadow)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_audit_rules_tc_shadow_open_by_handle_at_64bit_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_shadow_open_by_handle_at_64bit_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F[\s]+a2&03)[\s]+(?:-F[\s]+path=/etc/shadow)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

defined audit rule must exist  oval:ssg-test_audit_rules_tc_shadow_open_by_handle_at_32bit_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_shadow_open_by_handle_at_32bit_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F[\s]+a2&03)[\s]+(?:-F[\s]+path=/etc/shadow)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_audit_rules_tc_shadow_open_by_handle_at_64bit_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_shadow_open_by_handle_at_64bit_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(open_by_handle_at)(?:,[\S]+)*)[\s]+(?:-F[\s]+a2&03)[\s]+(?:-F[\s]+path=/etc/shadow)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$/etc/audit/audit.rules1
Record Events that Modify User/Group Information via openat syscall - /etc/shadowxccdf_org.ssgproject.content_rule_audit_rules_etc_shadow_openat medium

Record Events that Modify User/Group Information via openat syscall - /etc/shadow

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_etc_shadow_openat
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_etc_shadow_openat:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3, AC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a), FAU_GEN.1.1.c

Description
The audit system should collect write events to /etc/shadow file for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S openat -F a2&03 -F path=/etc/shadow -F auid>=1000 -F auid!=unset -F key=user-modify
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S openat -F a2&03 -F path=/etc/shadow -F auid>=1000 -F auid!=unset -F key=user-modify
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S openat -F a2&03 -F path=/etc/shadow -F auid>=1000 -F auid!=unset -F key=user-modify
Rationale
Creation of users through direct edition of /etc/shadow could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping system calls related to the same event is more efficient. See the following example:
-a always,exit -F arch=b32 -S open,openat,open_by_handle_at -F a2&03 -F path=/etc/shadow -F auid>=1000 -F auid!=unset -F key=user-modify

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F a2&03 -F path=/etc/shadow"
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="openat"
	KEY="user-modify"
	SYSCALL_GROUPING=""
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_shadow_openat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit openat tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_shadow_openat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for openat for x86 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - openat
        syscall_grouping: []

    - name: Check existence of openat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a2&03 -F path=/etc/shadow -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/modify.rules
      set_fact: audit_file="/etc/audit/rules.d/modify.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a2&03 -F path=/etc/shadow -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F a2&03 -F
          path=/etc/shadow -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - openat
        syscall_grouping: []

    - name: Check existence of openat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a2&03 -F path=/etc/shadow -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a2&03 -F path=/etc/shadow -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F a2&03 -F
          path=/etc/shadow -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_shadow_openat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Perform remediation of Audit rules for openat for x86_64 platform
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - openat
        syscall_grouping: []

    - name: Check existence of openat in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a2&03 -F path=/etc/shadow -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/modify.rules
      set_fact: audit_file="/etc/audit/rules.d/modify.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a2&03 -F path=/etc/shadow -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F a2&03 -F
          path=/etc/shadow -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls:
          - openat
        syscall_grouping: []

    - name: Check existence of openat in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+((
          -S |,)\w+)* -F a2&03 -F path=/etc/shadow -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a2&03 -F path=/etc/shadow -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F a2&03 -F
          path=/etc/shadow -F auid>=1000 -F auid!=unset -F key=modify
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - audit_arch == "b64"
  tags:
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - audit_rules_etc_shadow_openat
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

defined audit rule must exist  oval:ssg-test_audit_rules_tc_shadow_openat_32bit_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_shadow_openat_32bit_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F[\s]+a2&03)[\s]+(?:-F[\s]+path=/etc/shadow)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$^/etc/audit/rules\.d/.*\.rules$1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_audit_rules_tc_shadow_openat_64bit_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_shadow_openat_64bit_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F[\s]+a2&03)[\s]+(?:-F[\s]+path=/etc/shadow)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

defined audit rule must exist  oval:ssg-test_audit_rules_tc_shadow_openat_32bit_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_shadow_openat_32bit_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b32[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F[\s]+a2&03)[\s]+(?:-F[\s]+path=/etc/shadow)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$/etc/audit/audit.rules1

64 bit architecture  oval:ssg-test_system_info_architecture_x86_64:tst:1  true

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppc_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_ppcle_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_aarch_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

64 bit architecture  oval:ssg-test_system_info_architecture_s390_64:tst:1  false

Following items have been found on the system:
Machine classNode nameOs nameOs releaseOs versionProcessor type
x86_64fedoraLinux5.11.12-300.fc34.x86_64#1 SMP Wed Apr 7 16:31:13 UTC 2021x86_64

defined audit rule must exist  oval:ssg-test_audit_rules_tc_shadow_openat_64bit_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_tc_shadow_openat_64bit_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+arch=b64[\s]+)(?:-S[\s]+(?:[\S]+,)*(openat)(?:,[\S]+)*)[\s]+(?:-F[\s]+a2&03)[\s]+(?:-F[\s]+path=/etc/shadow)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$/etc/audit/audit.rules1
Make the auditd Configuration Immutablexccdf_org.ssgproject.content_rule_audit_rules_immutable medium

Make the auditd Configuration Immutable

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_immutable
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_immutable:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 18, 19, 3, 4, 5, 6, 7, 8, 5.4.1.1, APO01.06, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, BAI03.05, BAI08.02, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS05.04, DSS05.07, DSS06.02, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.3.1, 3.4.3, CCI-000162, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.310(a)(2)(iv), 164.312(d), 164.310(d)(2)(iii), 164.312(b), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.7.3, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 2.1, SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 5.2, SR 6.1, A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.1.3, A.13.2.1, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5, AC-6(9), CM-6(a), DE.AE-3, DE.AE-5, ID.SC-4, PR.AC-4, PR.DS-5, PR.PT-1, RS.AN-1, RS.AN-4, Req-10.5.2, SRG-OS-000057-GPOS-00027, SRG-OS-000058-GPOS-00028, SRG-OS-000059-GPOS-00029

Description
If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d in order to make the auditd configuration immutable:
-e 2
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file in order to make the auditd configuration immutable:
-e 2
With this setting, a reboot will be required to change any audit rules.
Rationale
Making the audit configuration immutable prevents accidental as well as malicious modification of the audit rules, although it may be problematic if legitimate changes are needed during system operation

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# Traverse all of:
#
# /etc/audit/audit.rules,			(for auditctl case)
# /etc/audit/rules.d/*.rules			(for augenrules case)
#
# files to check if '-e .*' setting is present in that '*.rules' file already.
# If found, delete such occurrence since auditctl(8) manual page instructs the
# '-e 2' rule should be placed as the last rule in the configuration
find /etc/audit /etc/audit/rules.d -maxdepth 1 -type f -name '*.rules' -exec sed -i '/-e[[:space:]]\+.*/d' {} ';'

# Append '-e 2' requirement at the end of both:
# * /etc/audit/audit.rules file 		(for auditctl case)
# * /etc/audit/rules.d/immutable.rules		(for augenrules case)

for AUDIT_FILE in "/etc/audit/audit.rules" "/etc/audit/rules.d/immutable.rules"
do
	echo '' >> $AUDIT_FILE
	echo '# Set the audit.rules configuration immutable per security requirements' >> $AUDIT_FILE
	echo '# Reboot is required to change audit rules once this setting is applied' >> $AUDIT_FILE
	echo '-e 2' >> $AUDIT_FILE
	chmod o-rwx $AUDIT_FILE
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.3.1
    - NIST-800-171-3.4.3
    - NIST-800-53-AC-6(9)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.2
    - audit_rules_immutable
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Collect all files from /etc/audit/rules.d with .rules extension
  find:
    paths: /etc/audit/rules.d/
    patterns: '*.rules'
  register: find_rules_d
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.3.1
    - NIST-800-171-3.4.3
    - NIST-800-53-AC-6(9)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.2
    - audit_rules_immutable
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Remove the -e option from all Audit config files
  lineinfile:
    path: '{{ item }}'
    regexp: ^\s*(?:-e)\s+.*$
    state: absent
  loop: '{{ find_rules_d.files | map(attribute=''path'') | list + [''/etc/audit/audit.rules'']
    }}'
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.3.1
    - NIST-800-171-3.4.3
    - NIST-800-53-AC-6(9)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.2
    - audit_rules_immutable
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Add Audit -e option into /etc/audit/rules.d/immutable.rules and /etc/audit/audit.rules
  lineinfile:
    path: '{{ item }}'
    create: true
    line: -e 2
    mode: o-rwx
  loop:
    - /etc/audit/audit.rules
    - /etc/audit/rules.d/immutable.rules
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.3.1
    - NIST-800-171-3.4.3
    - NIST-800-53-AC-6(9)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.2
    - audit_rules_immutable
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,-e%202%0A
        mode: 0600
        path: /etc/audit/rules.d/90-immutable.rules
        overwrite: true
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules configuration locked  oval:ssg-test_ari_locked_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_ari_locked_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^\-e\s+2\s*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl configuration locked  oval:ssg-test_ari_locked_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_ari_locked_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^\-e\s+2\s*$1
Record Events that Modify the System's Mandatory Access Controlsxccdf_org.ssgproject.content_rule_audit_rules_mac_modification medium

Record Events that Modify the System's Mandatory Access Controls

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_mac_modification
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_mac_modification:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, 5.4.1.1, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.8, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.5.5

Description
If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:
-w /etc/selinux/ -p wa -k MAC-policy
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-w /etc/selinux/ -p wa -k MAC-policy
Rationale
The system's mandatory access policy (SELinux) should not be arbitrarily changed by anything other than administrator action. All changes to MAC policy should be audited.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()


# If the audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# into the list of files to be inspected
files_to_inspect+=('/etc/audit/audit.rules')

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "[\s]*-w[\s]+/etc/selinux/" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/selinux/ $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/selinux/$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/selinux/ -p wa -k MAC-policy" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()

# If the audit is 'augenrules', then check if rule is already defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to list of files for inspection.
# If rule isn't defined, add '/etc/audit/rules.d/MAC-policy.rules' to list of files for inspection.
readarray -t matches < <(grep -HP "[\s]*-w[\s]+/etc/selinux/" /etc/audit/rules.d/*.rules)

# For each of the matched entries
for match in "${matches[@]}"
do
    # Extract filepath from the match
    rulesd_audit_file=$(echo $match | cut -f1 -d ':')
    # Append that path into list of files for inspection
    files_to_inspect+=("$rulesd_audit_file")
done
# Case when particular audit rule isn't defined yet
if [ "${#files_to_inspect[@]}" -eq "0" ]
then
    # Append '/etc/audit/rules.d/MAC-policy.rules' into list of files for inspection
    key_rule_file="/etc/audit/rules.d/MAC-policy.rules"
    # If the MAC-policy.rules file doesn't exist yet, create it with correct permissions
    if [ ! -e "$key_rule_file" ]
    then
        touch "$key_rule_file"
        chmod 0640 "$key_rule_file"
    fi
    files_to_inspect+=("$key_rule_file")
fi

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "[\s]*-w[\s]+/etc/selinux/" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/selinux/ $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/selinux/$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/selinux/ -p wa -k MAC-policy" >> "$audit_rules_file"
    fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.8
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_mac_modification
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Check if watch rule for /etc/selinux/ already exists in /etc/audit/rules.d/
  find:
    paths: /etc/audit/rules.d
    contains: ^\s*-w\s+/etc/selinux/\s+-p\s+wa(\s|$)+
    patterns: '*.rules'
  register: find_existing_watch_rules_d
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.8
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_mac_modification
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Search /etc/audit/rules.d for other rules with specified key MAC-policy
  find:
    paths: /etc/audit/rules.d
    contains: ^.*(?:-F key=|-k\s+)MAC-policy$
    patterns: '*.rules'
  register: find_watch_key
  when:
    - '"audit" in ansible_facts.packages'
    - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
      == 0
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.8
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_mac_modification
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Use /etc/audit/rules.d/MAC-policy.rules as the recipient for the rule
  set_fact:
    all_files:
      - /etc/audit/rules.d/MAC-policy.rules
  when:
    - '"audit" in ansible_facts.packages'
    - find_watch_key.matched is defined and find_watch_key.matched == 0 and find_existing_watch_rules_d.matched
      is defined and find_existing_watch_rules_d.matched == 0
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.8
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_mac_modification
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Use matched file as the recipient for the rule
  set_fact:
    all_files:
      - '{{ find_watch_key.files | map(attribute=''path'') | list | first }}'
  when:
    - '"audit" in ansible_facts.packages'
    - find_watch_key.matched is defined and find_watch_key.matched > 0 and find_existing_watch_rules_d.matched
      is defined and find_existing_watch_rules_d.matched == 0
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.8
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_mac_modification
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Add watch rule for /etc/selinux/ in /etc/audit/rules.d/
  lineinfile:
    path: '{{ all_files[0] }}'
    line: -w /etc/selinux/ -p wa -k MAC-policy
    create: true
    mode: '0640'
  when:
    - '"audit" in ansible_facts.packages'
    - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
      == 0
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.8
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_mac_modification
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Check if watch rule for /etc/selinux/ already exists in /etc/audit/audit.rules
  find:
    paths: /etc/audit/
    contains: ^\s*-w\s+/etc/selinux/\s+-p\s+wa(\s|$)+
    patterns: audit.rules
  register: find_existing_watch_audit_rules
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.8
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_mac_modification
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Add watch rule for /etc/selinux/ in /etc/audit/audit.rules
  lineinfile:
    line: -w /etc/selinux/ -p wa -k MAC-policy
    state: present
    dest: /etc/audit/audit.rules
    create: true
    mode: '0640'
  when:
    - '"audit" in ansible_facts.packages'
    - find_existing_watch_audit_rules.matched is defined and find_existing_watch_audit_rules.matched
      == 0
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.8
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.5
    - audit_rules_mac_modification
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
---

apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,{{ -w%20/etc/selinux/%20-p%20wa%20-k%20MAC-policy%0A }}
        mode: 0600
        path: /etc/audit/rules.d/75-etcselinux-wa-MAC-policy.rules
        overwrite: true
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit selinux changes augenrules  oval:ssg-test_armm_selinux_watch_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_armm_selinux_watch_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^\-w[\s]+/etc/selinux/[\s]+\-p[\s]+\b([rx]*w[rx]*a[rx]*|[rx]*a[rx]*w[rx]*)\b[\s]+(-k[\s]+|-F[\s]+key=)[-\w]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit selinux changes auditctl  oval:ssg-test_armm_selinux_watch_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_armm_selinux_watch_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^\-w[\s]+/etc/selinux/[\s]+\-p[\s]+\b([rx]*w[rx]*a[rx]*|[rx]*a[rx]*w[rx]*)\b[\s]+(-k[\s]+|-F[\s]+key=)[-\w]+[\s]*$1
Record Attempts to Alter Process and Session Initiation Informationxccdf_org.ssgproject.content_rule_audit_rules_session_events medium

Record Attempts to Alter Process and Session Initiation Information

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_session_events
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_session_events:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9, 5.4.1.1, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, 0582, 0584, 05885, 0586, 0846, 0957, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AU-2(d), AU-12(c), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.2.3

Description
The audit system already collects process information for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d in order to watch for attempted manual edits of files involved in storing such process information:
-w /var/run/utmp -p wa -k session
-w /var/log/btmp -p wa -k session
-w /var/log/wtmp -p wa -k session
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file in order to watch for attempted manual edits of files involved in storing such process information:
-w /var/run/utmp -p wa -k session
-w /var/log/btmp -p wa -k session
-w /var/log/wtmp -p wa -k session
Rationale
Manual editing of these files may indicate nefarious activity, such as an attacker attempting to remove evidence of an intrusion.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()


# If the audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# into the list of files to be inspected
files_to_inspect+=('/etc/audit/audit.rules')

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "[\s]*-w[\s]+/var/run/utmp" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/var/run/utmp $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/var/run/utmp$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /var/run/utmp -p wa -k session" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()

# If the audit is 'augenrules', then check if rule is already defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to list of files for inspection.
# If rule isn't defined, add '/etc/audit/rules.d/session.rules' to list of files for inspection.
readarray -t matches < <(grep -HP "[\s]*-w[\s]+/var/run/utmp" /etc/audit/rules.d/*.rules)

# For each of the matched entries
for match in "${matches[@]}"
do
    # Extract filepath from the match
    rulesd_audit_file=$(echo $match | cut -f1 -d ':')
    # Append that path into list of files for inspection
    files_to_inspect+=("$rulesd_audit_file")
done
# Case when particular audit rule isn't defined yet
if [ "${#files_to_inspect[@]}" -eq "0" ]
then
    # Append '/etc/audit/rules.d/session.rules' into list of files for inspection
    key_rule_file="/etc/audit/rules.d/session.rules"
    # If the session.rules file doesn't exist yet, create it with correct permissions
    if [ ! -e "$key_rule_file" ]
    then
        touch "$key_rule_file"
        chmod 0640 "$key_rule_file"
    fi
    files_to_inspect+=("$key_rule_file")
fi

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "[\s]*-w[\s]+/var/run/utmp" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/var/run/utmp $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/var/run/utmp$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /var/run/utmp -p wa -k session" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()


# If the audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# into the list of files to be inspected
files_to_inspect+=('/etc/audit/audit.rules')

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "[\s]*-w[\s]+/var/log/btmp" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/var/log/btmp $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/var/log/btmp$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /var/log/btmp -p wa -k session" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()

# If the audit is 'augenrules', then check if rule is already defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to list of files for inspection.
# If rule isn't defined, add '/etc/audit/rules.d/session.rules' to list of files for inspection.
readarray -t matches < <(grep -HP "[\s]*-w[\s]+/var/log/btmp" /etc/audit/rules.d/*.rules)

# For each of the matched entries
for match in "${matches[@]}"
do
    # Extract filepath from the match
    rulesd_audit_file=$(echo $match | cut -f1 -d ':')
    # Append that path into list of files for inspection
    files_to_inspect+=("$rulesd_audit_file")
done
# Case when particular audit rule isn't defined yet
if [ "${#files_to_inspect[@]}" -eq "0" ]
then
    # Append '/etc/audit/rules.d/session.rules' into list of files for inspection
    key_rule_file="/etc/audit/rules.d/session.rules"
    # If the session.rules file doesn't exist yet, create it with correct permissions
    if [ ! -e "$key_rule_file" ]
    then
        touch "$key_rule_file"
        chmod 0640 "$key_rule_file"
    fi
    files_to_inspect+=("$key_rule_file")
fi

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "[\s]*-w[\s]+/var/log/btmp" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/var/log/btmp $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/var/log/btmp$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /var/log/btmp -p wa -k session" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()


# If the audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# into the list of files to be inspected
files_to_inspect+=('/etc/audit/audit.rules')

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "[\s]*-w[\s]+/var/log/wtmp" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/var/log/wtmp $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/var/log/wtmp$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /var/log/wtmp -p wa -k session" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()

# If the audit is 'augenrules', then check if rule is already defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to list of files for inspection.
# If rule isn't defined, add '/etc/audit/rules.d/session.rules' to list of files for inspection.
readarray -t matches < <(grep -HP "[\s]*-w[\s]+/var/log/wtmp" /etc/audit/rules.d/*.rules)

# For each of the matched entries
for match in "${matches[@]}"
do
    # Extract filepath from the match
    rulesd_audit_file=$(echo $match | cut -f1 -d ':')
    # Append that path into list of files for inspection
    files_to_inspect+=("$rulesd_audit_file")
done
# Case when particular audit rule isn't defined yet
if [ "${#files_to_inspect[@]}" -eq "0" ]
then
    # Append '/etc/audit/rules.d/session.rules' into list of files for inspection
    key_rule_file="/etc/audit/rules.d/session.rules"
    # If the session.rules file doesn't exist yet, create it with correct permissions
    if [ ! -e "$key_rule_file" ]
    then
        touch "$key_rule_file"
        chmod 0640 "$key_rule_file"
    fi
    files_to_inspect+=("$key_rule_file")
fi

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "[\s]*-w[\s]+/var/log/wtmp" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/var/log/wtmp $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/var/log/wtmp$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /var/log/wtmp -p wa -k session" >> "$audit_rules_file"
    fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.3
    - audit_rules_session_events
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Check if watch rule for /var/run/utmp already exists in /etc/audit/rules.d/
  find:
    paths: /etc/audit/rules.d
    contains: ^\s*-w\s+/var/run/utmp\s+-p\s+wa(\s|$)+
    patterns: '*.rules'
  register: find_existing_watch_rules_d
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.3
    - audit_rules_session_events
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Search /etc/audit/rules.d for other rules with specified key session
  find:
    paths: /etc/audit/rules.d
    contains: ^.*(?:-F key=|-k\s+)session$
    patterns: '*.rules'
  register: find_watch_key
  when:
    - '"audit" in ansible_facts.packages'
    - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
      == 0
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.3
    - audit_rules_session_events
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Use /etc/audit/rules.d/session.rules as the recipient for the rule
  set_fact:
    all_files:
      - /etc/audit/rules.d/session.rules
  when:
    - '"audit" in ansible_facts.packages'
    - find_watch_key.matched is defined and find_watch_key.matched == 0 and find_existing_watch_rules_d.matched
      is defined and find_existing_watch_rules_d.matched == 0
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.3
    - audit_rules_session_events
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Use matched file as the recipient for the rule
  set_fact:
    all_files:
      - '{{ find_watch_key.files | map(attribute=''path'') | list | first }}'
  when:
    - '"audit" in ansible_facts.packages'
    - find_watch_key.matched is defined and find_watch_key.matched > 0 and find_existing_watch_rules_d.matched
      is defined and find_existing_watch_rules_d.matched == 0
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.3
    - audit_rules_session_events
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Add watch rule for /var/run/utmp in /etc/audit/rules.d/
  lineinfile:
    path: '{{ all_files[0] }}'
    line: -w /var/run/utmp -p wa -k session
    create: true
    mode: '0640'
  when:
    - '"audit" in ansible_facts.packages'
    - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
      == 0
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.3
    - audit_rules_session_events
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Check if watch rule for /var/run/utmp already exists in /etc/audit/audit.rules
  find:
    paths: /etc/audit/
    contains: ^\s*-w\s+/var/run/utmp\s+-p\s+wa(\s|$)+
    patterns: audit.rules
  register: find_existing_watch_audit_rules
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.3
    - audit_rules_session_events
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Add watch rule for /var/run/utmp in /etc/audit/audit.rules
  lineinfile:
    line: -w /var/run/utmp -p wa -k session
    state: present
    dest: /etc/audit/audit.rules
    create: true
    mode: '0640'
  when:
    - '"audit" in ansible_facts.packages'
    - find_existing_watch_audit_rules.matched is defined and find_existing_watch_audit_rules.matched
      == 0
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.3
    - audit_rules_session_events
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Check if watch rule for /var/log/btmp already exists in /etc/audit/rules.d/
  find:
    paths: /etc/audit/rules.d
    contains: ^\s*-w\s+/var/log/btmp\s+-p\s+wa(\s|$)+
    patterns: '*.rules'
  register: find_existing_watch_rules_d
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.3
    - audit_rules_session_events
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Search /etc/audit/rules.d for other rules with specified key session
  find:
    paths: /etc/audit/rules.d
    contains: ^.*(?:-F key=|-k\s+)session$
    patterns: '*.rules'
  register: find_watch_key
  when:
    - '"audit" in ansible_facts.packages'
    - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
      == 0
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.3
    - audit_rules_session_events
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Use /etc/audit/rules.d/session.rules as the recipient for the rule
  set_fact:
    all_files:
      - /etc/audit/rules.d/session.rules
  when:
    - '"audit" in ansible_facts.packages'
    - find_watch_key.matched is defined and find_watch_key.matched == 0 and find_existing_watch_rules_d.matched
      is defined and find_existing_watch_rules_d.matched == 0
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.3
    - audit_rules_session_events
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Use matched file as the recipient for the rule
  set_fact:
    all_files:
      - '{{ find_watch_key.files | map(attribute=''path'') | list | first }}'
  when:
    - '"audit" in ansible_facts.packages'
    - find_watch_key.matched is defined and find_watch_key.matched > 0 and find_existing_watch_rules_d.matched
      is defined and find_existing_watch_rules_d.matched == 0
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.3
    - audit_rules_session_events
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Add watch rule for /var/log/btmp in /etc/audit/rules.d/
  lineinfile:
    path: '{{ all_files[0] }}'
    line: -w /var/log/btmp -p wa -k session
    create: true
    mode: '0640'
  when:
    - '"audit" in ansible_facts.packages'
    - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
      == 0
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.3
    - audit_rules_session_events
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Check if watch rule for /var/log/btmp already exists in /etc/audit/audit.rules
  find:
    paths: /etc/audit/
    contains: ^\s*-w\s+/var/log/btmp\s+-p\s+wa(\s|$)+
    patterns: audit.rules
  register: find_existing_watch_audit_rules
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.3
    - audit_rules_session_events
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Add watch rule for /var/log/btmp in /etc/audit/audit.rules
  lineinfile:
    line: -w /var/log/btmp -p wa -k session
    state: present
    dest: /etc/audit/audit.rules
    create: true
    mode: '0640'
  when:
    - '"audit" in ansible_facts.packages'
    - find_existing_watch_audit_rules.matched is defined and find_existing_watch_audit_rules.matched
      == 0
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.3
    - audit_rules_session_events
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Check if watch rule for /var/log/wtmp already exists in /etc/audit/rules.d/
  find:
    paths: /etc/audit/rules.d
    contains: ^\s*-w\s+/var/log/wtmp\s+-p\s+wa(\s|$)+
    patterns: '*.rules'
  register: find_existing_watch_rules_d
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.3
    - audit_rules_session_events
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Search /etc/audit/rules.d for other rules with specified key session
  find:
    paths: /etc/audit/rules.d
    contains: ^.*(?:-F key=|-k\s+)session$
    patterns: '*.rules'
  register: find_watch_key
  when:
    - '"audit" in ansible_facts.packages'
    - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
      == 0
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.3
    - audit_rules_session_events
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Use /etc/audit/rules.d/session.rules as the recipient for the rule
  set_fact:
    all_files:
      - /etc/audit/rules.d/session.rules
  when:
    - '"audit" in ansible_facts.packages'
    - find_watch_key.matched is defined and find_watch_key.matched == 0 and find_existing_watch_rules_d.matched
      is defined and find_existing_watch_rules_d.matched == 0
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.3
    - audit_rules_session_events
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Use matched file as the recipient for the rule
  set_fact:
    all_files:
      - '{{ find_watch_key.files | map(attribute=''path'') | list | first }}'
  when:
    - '"audit" in ansible_facts.packages'
    - find_watch_key.matched is defined and find_watch_key.matched > 0 and find_existing_watch_rules_d.matched
      is defined and find_existing_watch_rules_d.matched == 0
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.3
    - audit_rules_session_events
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Add watch rule for /var/log/wtmp in /etc/audit/rules.d/
  lineinfile:
    path: '{{ all_files[0] }}'
    line: -w /var/log/wtmp -p wa -k session
    create: true
    mode: '0640'
  when:
    - '"audit" in ansible_facts.packages'
    - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
      == 0
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.3
    - audit_rules_session_events
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Check if watch rule for /var/log/wtmp already exists in /etc/audit/audit.rules
  find:
    paths: /etc/audit/
    contains: ^\s*-w\s+/var/log/wtmp\s+-p\s+wa(\s|$)+
    patterns: audit.rules
  register: find_existing_watch_audit_rules
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.3
    - audit_rules_session_events
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Add watch rule for /var/log/wtmp in /etc/audit/audit.rules
  lineinfile:
    line: -w /var/log/wtmp -p wa -k session
    state: present
    dest: /etc/audit/audit.rules
    create: true
    mode: '0640'
  when:
    - '"audit" in ansible_facts.packages'
    - find_existing_watch_audit_rules.matched is defined and find_existing_watch_audit_rules.matched
      == 0
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.3
    - audit_rules_session_events
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
---


apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,{{ %0A-w%20/var/run/utmp%20-p%20wa%20-k%20session%0A-w%20/var/log/btmp%20-p%20wa%20-k%20session%0A-w%20/var/log/wtmp%20-p%20wa%20-k%20session%0A }}
        mode: 0600
        path: /etc/audit/rules.d/75-audit-session-events.rules
        overwrite: true
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules utmp  oval:ssg-test_arse_utmp_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arse_utmp_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^\-w\s+/var/run/utmp\s+\-p\s+wa\s+(-k[\s]+|-F[\s]+key=)[-\w]+\s*$1

audit augenrules btmp  oval:ssg-test_arse_btmp_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arse_btmp_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^\-w\s+/var/log/btmp\s+\-p\s+wa\s+(-k[\s]+|-F[\s]+key=)[-\w]+\s*$1

audit augenrules wtmp  oval:ssg-test_arse_wtmp_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arse_wtmp_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^\-w\s+/var/log/wtmp\s+\-p\s+wa\s+(-k[\s]+|-F[\s]+key=)[-\w]+\s*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl utmp  oval:ssg-test_arse_utmp_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arse_utmp_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^\-w\s+/var/run/utmp\s+\-p\s+wa\s+(-k[\s]+|-F[\s]+key=)[-\w]+\s*$1

audit auditctl btmp  oval:ssg-test_arse_btmp_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arse_btmp_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^\-w\s+/var/log/btmp\s+\-p\s+wa\s+(-k[\s]+|-F[\s]+key=)[-\w]+\s*$1

audit auditctl wtmp  oval:ssg-test_arse_wtmp_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_arse_wtmp_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^\-w\s+/var/log/wtmp\s+\-p\s+wa\s+(-k[\s]+|-F[\s]+key=)[-\w]+\s*$1
Ensure auditd Collects System Administrator Actionsxccdf_org.ssgproject.content_rule_audit_rules_sysadmin_actions medium

Ensure auditd Collects System Administrator Actions

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_sysadmin_actions
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_sysadmin_actions:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 18, 19, 2, 3, 4, 5, 6, 7, 8, 9, 5.4.1.1, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, DSS06.03, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000126, CCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.2.2, 4.3.3.3.9, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.8, 4.3.3.6.6, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.1, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.1.2, A.6.2.1, A.6.2.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.1, A.9.4.2, A.9.4.3, A.9.4.4, A.9.4.5, AC-2(7)(b), AU-2(d), AU-12(c), AC-6(9), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-1, PR.AC-3, PR.AC-4, PR.AC-6, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.2.2, Req-10.2.5.b, SRG-OS-000004-GPOS-00004, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000304-GPOS-00121, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000470-GPOS-00214, SRG-OS-000471-GPOS-00215, SRG-OS-000239-GPOS-00089, SRG-OS-000240-GPOS-00090, SRG-OS-000241-GPOS-00091, SRG-OS-000303-GPOS-00120, SRG-OS-000304-GPOS-00121, SRG-OS-000466-GPOS-00210, SRG-OS-000476-GPOS-00221, SRG-OS-000462-VMM-001840, SRG-OS-000471-VMM-001910

Description
At a minimum, the audit system should collect administrator actions for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:
-w /etc/sudoers -p wa -k actions
-w /etc/sudoers.d/ -p wa -k actions
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-w /etc/sudoers -p wa -k actions
-w /etc/sudoers.d/ -p wa -k actions
Rationale
The actions taken by system administrators should be audited to keep a record of what was executed on the system, as well as, for accountability purposes.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()


# If the audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# into the list of files to be inspected
files_to_inspect+=('/etc/audit/audit.rules')

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "[\s]*-w[\s]+/etc/sudoers" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/sudoers $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/sudoers$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/sudoers -p wa -k actions" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()

# If the audit is 'augenrules', then check if rule is already defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to list of files for inspection.
# If rule isn't defined, add '/etc/audit/rules.d/actions.rules' to list of files for inspection.
readarray -t matches < <(grep -HP "[\s]*-w[\s]+/etc/sudoers" /etc/audit/rules.d/*.rules)

# For each of the matched entries
for match in "${matches[@]}"
do
    # Extract filepath from the match
    rulesd_audit_file=$(echo $match | cut -f1 -d ':')
    # Append that path into list of files for inspection
    files_to_inspect+=("$rulesd_audit_file")
done
# Case when particular audit rule isn't defined yet
if [ "${#files_to_inspect[@]}" -eq "0" ]
then
    # Append '/etc/audit/rules.d/actions.rules' into list of files for inspection
    key_rule_file="/etc/audit/rules.d/actions.rules"
    # If the actions.rules file doesn't exist yet, create it with correct permissions
    if [ ! -e "$key_rule_file" ]
    then
        touch "$key_rule_file"
        chmod 0640 "$key_rule_file"
    fi
    files_to_inspect+=("$key_rule_file")
fi

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "[\s]*-w[\s]+/etc/sudoers" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/sudoers $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/sudoers$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/sudoers -p wa -k actions" >> "$audit_rules_file"
    fi
done

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()


# If the audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# into the list of files to be inspected
files_to_inspect+=('/etc/audit/audit.rules')

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "[\s]*-w[\s]+/etc/sudoers.d/" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/sudoers.d/ $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/sudoers.d/$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/sudoers.d/ -p wa -k actions" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()

# If the audit is 'augenrules', then check if rule is already defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to list of files for inspection.
# If rule isn't defined, add '/etc/audit/rules.d/actions.rules' to list of files for inspection.
readarray -t matches < <(grep -HP "[\s]*-w[\s]+/etc/sudoers.d/" /etc/audit/rules.d/*.rules)

# For each of the matched entries
for match in "${matches[@]}"
do
    # Extract filepath from the match
    rulesd_audit_file=$(echo $match | cut -f1 -d ':')
    # Append that path into list of files for inspection
    files_to_inspect+=("$rulesd_audit_file")
done
# Case when particular audit rule isn't defined yet
if [ "${#files_to_inspect[@]}" -eq "0" ]
then
    # Append '/etc/audit/rules.d/actions.rules' into list of files for inspection
    key_rule_file="/etc/audit/rules.d/actions.rules"
    # If the actions.rules file doesn't exist yet, create it with correct permissions
    if [ ! -e "$key_rule_file" ]
    then
        touch "$key_rule_file"
        chmod 0640 "$key_rule_file"
    fi
    files_to_inspect+=("$key_rule_file")
fi

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "[\s]*-w[\s]+/etc/sudoers.d/" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/sudoers.d/ $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/sudoers.d/$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/sudoers.d/ -p wa -k actions" >> "$audit_rules_file"
    fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(7)(b)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.2
    - PCI-DSS-Req-10.2.5.b
    - audit_rules_sysadmin_actions
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Search /etc/audit/rules.d for audit rule entries for sysadmin actions
  find:
    paths: /etc/audit/rules.d
    recurse: false
    contains: ^.*/etc/sudoers.*$
    patterns: '*.rules'
  register: find_audit_sysadmin_actions
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(7)(b)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.2
    - PCI-DSS-Req-10.2.5.b
    - audit_rules_sysadmin_actions
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Use /etc/audit/rules.d/actions.rules as the recipient for the rule
  set_fact:
    all_sysadmin_actions_files:
      - /etc/audit/rules.d/actions.rules
  when:
    - '"audit" in ansible_facts.packages'
    - find_audit_sysadmin_actions.matched is defined and find_audit_sysadmin_actions.matched
      == 0
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(7)(b)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.2
    - PCI-DSS-Req-10.2.5.b
    - audit_rules_sysadmin_actions
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Use matched file as the recipient for the rule
  set_fact:
    all_sysadmin_actions_files:
      - '{{ find_audit_sysadmin_actions.files | map(attribute=''path'') | list | first
        }}'
  when:
    - '"audit" in ansible_facts.packages'
    - find_audit_sysadmin_actions.matched is defined and find_audit_sysadmin_actions.matched
      > 0
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(7)(b)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.2
    - PCI-DSS-Req-10.2.5.b
    - audit_rules_sysadmin_actions
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Inserts/replaces audit rule for /etc/sudoers rule in rules.d
  lineinfile:
    path: '{{ all_sysadmin_actions_files[0] }}'
    line: -w /etc/sudoers -p wa -k actions
    create: true
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(7)(b)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.2
    - PCI-DSS-Req-10.2.5.b
    - audit_rules_sysadmin_actions
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Inserts/replaces audit rule for /etc/sudoers.d rule in rules.d
  lineinfile:
    path: '{{ all_sysadmin_actions_files[0] }}'
    line: -w /etc/sudoers.d/ -p wa -k actions
    create: true
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(7)(b)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.2
    - PCI-DSS-Req-10.2.5.b
    - audit_rules_sysadmin_actions
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Inserts/replaces audit rule for /etc/sudoers in audit.rules
  lineinfile:
    path: /etc/audit/audit.rules
    line: -w /etc/sudoers -p wa -k actions
    create: true
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(7)(b)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.2
    - PCI-DSS-Req-10.2.5.b
    - audit_rules_sysadmin_actions
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Inserts/replaces audit rule for /etc/sudoers.d in audit.rules
  lineinfile:
    path: /etc/audit/audit.rules
    line: -w /etc/sudoers.d/ -p wa -k actions
    create: true
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(7)(b)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.2
    - PCI-DSS-Req-10.2.5.b
    - audit_rules_sysadmin_actions
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,{{ -w%20/etc/sudoers.d/%20-p%20wa%20-k%20actions%0A-w%20/etc/sudoers%20-p%20wa%20-k%20actions%0A }}
        mode: 0600
        path: /etc/audit/rules.d/75-audit-sysadmin-actions.rules
        overwrite: true
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules sudoers  oval:ssg-test_audit_rules_sysadmin_actions_sudoers_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_sysadmin_actions_sudoers_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^\-w[\s]+/etc/sudoers[\s]+\-p[\s]+\b([rx]*w[rx]*a[rx]*|[rx]*a[rx]*w[rx]*)\b[\s]+(-k[\s]+|-F[\s]+key=)[-\w]+[\s]*$1

audit augenrules sudoers  oval:ssg-test_audit_rules_sysadmin_actions_sudoers_d_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_sysadmin_actions_sudoers_d_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^\-w[\s]+/etc/sudoers\.d/[\s]+\-p[\s]+\b([rx]*w[rx]*a[rx]*|[rx]*a[rx]*w[rx]*)\b[\s]+(-k[\s]+|-F[\s]+key=)[-\w]+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit auditctl sudoers  oval:ssg-test_audit_rules_sysadmin_actions_sudoers_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_sysadmin_actions_sudoers_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^\-w[\s]+/etc/sudoers[\s]+\-p[\s]+\b([rx]*w[rx]*a[rx]*|[rx]*a[rx]*w[rx]*)\b[\s]+(-k[\s]+|-F[\s]+key=)[-\w]+[\s]*$1

audit auditctl sudoers  oval:ssg-test_audit_rules_sysadmin_actions_sudoers_d_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_sysadmin_actions_sudoers_d_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^\-w[\s]+/etc/sudoers\.d/[\s]+\-p[\s]+\b([rx]*w[rx]*a[rx]*|[rx]*a[rx]*w[rx]*)\b[\s]+(-k[\s]+|-F[\s]+key=)[-\w]+[\s]*$1
Record Events that Modify User/Group Information - /etc/groupxccdf_org.ssgproject.content_rule_audit_rules_usergroup_modification_group medium

Record Events that Modify User/Group Information - /etc/group

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_usergroup_modification_group
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_usergroup_modification_group:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 18, 19, 2, 3, 4, 5, 6, 7, 8, 9, 5.4.1.1, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, DSS06.03, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000018, CCI-000169, CCI-000172, CCI-001403, CCI-001404, CCI-001405, CCI-001683, CCI-001684, CCI-001685, CCI-001686, CCI-002130, CCI-002132, CCI-002884, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.2.2, 4.3.3.3.9, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.8, 4.3.3.6.6, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.1, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.1.2, A.6.2.1, A.6.2.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.1, A.9.4.2, A.9.4.3, A.9.4.4, A.9.4.5, CIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3, AC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-1, PR.AC-3, PR.AC-4, PR.AC-6, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.2.5, SRG-OS-000004-GPOS-00004, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000304-GPOS-00121, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000470-GPOS-00214, SRG-OS-000471-GPOS-00215, SRG-OS-000239-GPOS-00089, SRG-OS-000240-GPOS-00090, SRG-OS-000241-GPOS-00091, SRG-OS-000303-GPOS-00120, SRG-OS-000304-GPOS-00121, SRG-OS-000466-GPOS-00210, SRG-OS-000476-GPOS-00221, SRG-OS-000004-VMM-000040, SRG-OS-000239-VMM-000810, SRG-OS-000240-VMM-000820, SRG-OS-000241-VMM-000830, SRG-OS-000274-VMM-000960, SRG-OS-000275-VMM-000970, SRG-OS-000276-VMM-000980, SRG-OS-000277-VMM-000990, SRG-OS-000303-VMM-001090, SRG-OS-000304-VMM-001100, SRG-OS-000476-VMM-001960

Description
If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d, in order to capture events that modify account changes:

-w /etc/group -p wa -k audit_rules_usergroup_modification


If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file, in order to capture events that modify account changes:

-w /etc/group -p wa -k audit_rules_usergroup_modification
Rationale
In addition to auditing new user and group accounts, these watches will alert the system administrator(s) to any modifications. Any unexpected users, groups, or modifications should be investigated for legitimacy.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()


# If the audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# into the list of files to be inspected
files_to_inspect+=('/etc/audit/audit.rules')

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "[\s]*-w[\s]+/etc/group" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/group $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/group$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/group -p wa -k audit_rules_usergroup_modification" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()

# If the audit is 'augenrules', then check if rule is already defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to list of files for inspection.
# If rule isn't defined, add '/etc/audit/rules.d/audit_rules_usergroup_modification.rules' to list of files for inspection.
readarray -t matches < <(grep -HP "[\s]*-w[\s]+/etc/group" /etc/audit/rules.d/*.rules)

# For each of the matched entries
for match in "${matches[@]}"
do
    # Extract filepath from the match
    rulesd_audit_file=$(echo $match | cut -f1 -d ':')
    # Append that path into list of files for inspection
    files_to_inspect+=("$rulesd_audit_file")
done
# Case when particular audit rule isn't defined yet
if [ "${#files_to_inspect[@]}" -eq "0" ]
then
    # Append '/etc/audit/rules.d/audit_rules_usergroup_modification.rules' into list of files for inspection
    key_rule_file="/etc/audit/rules.d/audit_rules_usergroup_modification.rules"
    # If the audit_rules_usergroup_modification.rules file doesn't exist yet, create it with correct permissions
    if [ ! -e "$key_rule_file" ]
    then
        touch "$key_rule_file"
        chmod 0640 "$key_rule_file"
    fi
    files_to_inspect+=("$key_rule_file")
fi

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "[\s]*-w[\s]+/etc/group" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/group $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/group$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/group -p wa -k audit_rules_usergroup_modification" >> "$audit_rules_file"
    fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_group
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit group tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_group
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Search /etc/audit/rules.d for other user/group modification audit rules
  find:
    paths: /etc/audit/rules.d
    recurse: false
    contains: -k audit_rules_usergroup_modification$
    patterns: '*.rules'
  register: find_group
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_group
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: If existing user/group modification ruleset not found, use /etc/audit/rules.d/privileged.rules
    as the recipient for the rule
  set_fact:
    all_files:
      - /etc/audit/rules.d/privileged.rules
  when:
    - '"audit" in ansible_facts.packages'
    - find_group.matched is defined and find_group.matched == 0
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_group
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Use matched file as the recipient for the rule
  set_fact:
    all_files:
      - '{{ find_group.files | map(attribute=''path'') | list | first }}'
  when:
    - '"audit" in ansible_facts.packages'
    - find_group.matched is defined and find_group.matched > 0
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_group
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Inserts/replaces the group rule in rules.d when on x86
  lineinfile:
    path: '{{ all_files[0] }}'
    line: -w /etc/group -p wa -k audit_rules_usergroup_modification
    create: true
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_group
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Inserts/replaces the group rule in /etc/audit/audit.rules
  lineinfile:
    line: -w /etc/group -p wa -k audit_rules_usergroup_modification
    state: present
    dest: /etc/audit/audit.rules
    create: true
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_group
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules group  oval:ssg-test_audit_rules_usergroup_modification_group_augen:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_usergroup_modification_group_augen:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^\-w[\s]+\/etc\/group[\s]+\-p[\s]+\b([rx]*w[rx]*a[rx]*|[rx]*a[rx]*w[rx]*)\b[\s]+(-k[\s]+|-F[\s]+key=)\w+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit group  oval:ssg-test_audit_rules_usergroup_modification_group_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_usergroup_modification_group_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^\-w[\s]+\/etc\/group[\s]+\-p[\s]+\b([rx]*w[rx]*a[rx]*|[rx]*a[rx]*w[rx]*)\b[\s]+(-k[\s]+|-F[\s]+key=)\w+[\s]*$1
Record Events that Modify User/Group Information - /etc/gshadowxccdf_org.ssgproject.content_rule_audit_rules_usergroup_modification_gshadow medium

Record Events that Modify User/Group Information - /etc/gshadow

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_usergroup_modification_gshadow
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_usergroup_modification_gshadow:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 18, 19, 2, 3, 4, 5, 6, 7, 8, 9, 5.4.1.1, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, DSS06.03, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000018, CCI-000169, CCI-000172, CCI-001403, CCI-001404, CCI-001405, CCI-001683, CCI-001684, CCI-001685, CCI-001686, CCI-002130, CCI-002132, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.2.2, 4.3.3.3.9, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.8, 4.3.3.6.6, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.1, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.1.2, A.6.2.1, A.6.2.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.1, A.9.4.2, A.9.4.3, A.9.4.4, A.9.4.5, CIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3, AC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-1, PR.AC-3, PR.AC-4, PR.AC-6, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.2.5, SRG-OS-000004-GPOS-00004, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000304-GPOS-00121, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000470-GPOS-00214, SRG-OS-000471-GPOS-00215, SRG-OS-000239-GPOS-00089, SRG-OS-000240-GPOS-00090, SRG-OS-000241-GPOS-00091, SRG-OS-000303-GPOS-00120, SRG-OS-000304-GPOS-00121, SRG-OS-000466-GPOS-00210, SRG-OS-000476-GPOS-00221, SRG-OS-000004-VMM-000040, SRG-OS-000239-VMM-000810, SRG-OS-000240-VMM-000820, SRG-OS-000241-VMM-000830, SRG-OS-000274-VMM-000960, SRG-OS-000275-VMM-000970, SRG-OS-000276-VMM-000980, SRG-OS-000277-VMM-000990, SRG-OS-000303-VMM-001090, SRG-OS-000304-VMM-001100, SRG-OS-000476-VMM-001960

Description
If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d, in order to capture events that modify account changes:

-w /etc/gshadow -p wa -k audit_rules_usergroup_modification


If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file, in order to capture events that modify account changes:

-w /etc/gshadow -p wa -k audit_rules_usergroup_modification
Rationale
In addition to auditing new user and group accounts, these watches will alert the system administrator(s) to any modifications. Any unexpected users, groups, or modifications should be investigated for legitimacy.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()


# If the audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# into the list of files to be inspected
files_to_inspect+=('/etc/audit/audit.rules')

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "[\s]*-w[\s]+/etc/gshadow" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/gshadow $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/gshadow$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/gshadow -p wa -k audit_rules_usergroup_modification" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()

# If the audit is 'augenrules', then check if rule is already defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to list of files for inspection.
# If rule isn't defined, add '/etc/audit/rules.d/audit_rules_usergroup_modification.rules' to list of files for inspection.
readarray -t matches < <(grep -HP "[\s]*-w[\s]+/etc/gshadow" /etc/audit/rules.d/*.rules)

# For each of the matched entries
for match in "${matches[@]}"
do
    # Extract filepath from the match
    rulesd_audit_file=$(echo $match | cut -f1 -d ':')
    # Append that path into list of files for inspection
    files_to_inspect+=("$rulesd_audit_file")
done
# Case when particular audit rule isn't defined yet
if [ "${#files_to_inspect[@]}" -eq "0" ]
then
    # Append '/etc/audit/rules.d/audit_rules_usergroup_modification.rules' into list of files for inspection
    key_rule_file="/etc/audit/rules.d/audit_rules_usergroup_modification.rules"
    # If the audit_rules_usergroup_modification.rules file doesn't exist yet, create it with correct permissions
    if [ ! -e "$key_rule_file" ]
    then
        touch "$key_rule_file"
        chmod 0640 "$key_rule_file"
    fi
    files_to_inspect+=("$key_rule_file")
fi

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "[\s]*-w[\s]+/etc/gshadow" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/gshadow $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/gshadow$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/gshadow -p wa -k audit_rules_usergroup_modification" >> "$audit_rules_file"
    fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_gshadow
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit gshadow tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_gshadow
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Search /etc/audit/rules.d for other user/group modification audit rules
  find:
    paths: /etc/audit/rules.d
    recurse: false
    contains: -k audit_rules_usergroup_modification$
    patterns: '*.rules'
  register: find_gshadow
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_gshadow
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: If existing user/group modification ruleset not found, use /etc/audit/rules.d/privileged.rules
    as the recipient for the rule
  set_fact:
    all_files:
      - /etc/audit/rules.d/privileged.rules
  when:
    - '"audit" in ansible_facts.packages'
    - find_gshadow.matched is defined and find_gshadow.matched == 0
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_gshadow
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Use matched file as the recipient for the rule
  set_fact:
    all_files:
      - '{{ find_gshadow.files | map(attribute=''path'') | list | first }}'
  when:
    - '"audit" in ansible_facts.packages'
    - find_gshadow.matched is defined and find_gshadow.matched > 0
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_gshadow
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Inserts/replaces the gshadow rule in rules.d when on x86
  lineinfile:
    path: '{{ all_files[0] }}'
    line: -w /etc/gshadow -p wa -k audit_rules_usergroup_modification
    create: true
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_gshadow
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Inserts/replaces the gshadow rule in /etc/audit/audit.rules
  lineinfile:
    line: -w /etc/gshadow -p wa -k audit_rules_usergroup_modification
    state: present
    dest: /etc/audit/audit.rules
    create: true
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_gshadow
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules gshadow  oval:ssg-test_audit_rules_usergroup_modification_gshadow_augen:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_usergroup_modification_gshadow_augen:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^\-w[\s]+\/etc\/gshadow[\s]+\-p[\s]+\b([rx]*w[rx]*a[rx]*|[rx]*a[rx]*w[rx]*)\b[\s]+(-k[\s]+|-F[\s]+key=)\w+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit gshadow  oval:ssg-test_audit_rules_usergroup_modification_gshadow_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_usergroup_modification_gshadow_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^\-w[\s]+\/etc\/gshadow[\s]+\-p[\s]+\b([rx]*w[rx]*a[rx]*|[rx]*a[rx]*w[rx]*)\b[\s]+(-k[\s]+|-F[\s]+key=)\w+[\s]*$1
Record Events that Modify User/Group Information - /etc/security/opasswdxccdf_org.ssgproject.content_rule_audit_rules_usergroup_modification_opasswd medium

Record Events that Modify User/Group Information - /etc/security/opasswd

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_usergroup_modification_opasswd
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_usergroup_modification_opasswd:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 18, 19, 2, 3, 4, 5, 6, 7, 8, 9, 5.4.1.1, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, DSS06.03, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000018, CCI-000169, CCI-000172, CCI-001403, CCI-001404, CCI-001405, CCI-001683, CCI-001684, CCI-001685, CCI-001686, CCI-002130, CCI-002132, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.2.2, 4.3.3.3.9, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.8, 4.3.3.6.6, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.1, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.1.2, A.6.2.1, A.6.2.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.1, A.9.4.2, A.9.4.3, A.9.4.4, A.9.4.5, CIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3, AC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-1, PR.AC-3, PR.AC-4, PR.AC-6, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.2.5, SRG-OS-000004-GPOS-00004, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000304-GPOS-00121, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000470-GPOS-00214, SRG-OS-000471-GPOS-00215, SRG-OS-000239-GPOS-00089, SRG-OS-000240-GPOS-00090, SRG-OS-000241-GPOS-00091, SRG-OS-000303-GPOS-00120, SRG-OS-000304-GPOS-00121, SRG-OS-000476-GPOS-00221, SRG-OS-000463-GPOS-00207, SRG-OS-000004-VMM-000040, SRG-OS-000239-VMM-000810, SRG-OS-000240-VMM-000820, SRG-OS-000241-VMM-000830, SRG-OS-000274-VMM-000960, SRG-OS-000275-VMM-000970, SRG-OS-000276-VMM-000980, SRG-OS-000277-VMM-000990, SRG-OS-000303-VMM-001090, SRG-OS-000304-VMM-001100, SRG-OS-000476-VMM-001960

Description
If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d, in order to capture events that modify account changes:

-w /etc/security/opasswd -p wa -k audit_rules_usergroup_modification


If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file, in order to capture events that modify account changes:

-w /etc/security/opasswd -p wa -k audit_rules_usergroup_modification
Rationale
In addition to auditing new user and group accounts, these watches will alert the system administrator(s) to any modifications. Any unexpected users, groups, or modifications should be investigated for legitimacy.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()


# If the audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# into the list of files to be inspected
files_to_inspect+=('/etc/audit/audit.rules')

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "[\s]*-w[\s]+/etc/security/opasswd" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/security/opasswd $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/security/opasswd$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/security/opasswd -p wa -k audit_rules_usergroup_modification" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()

# If the audit is 'augenrules', then check if rule is already defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to list of files for inspection.
# If rule isn't defined, add '/etc/audit/rules.d/audit_rules_usergroup_modification.rules' to list of files for inspection.
readarray -t matches < <(grep -HP "[\s]*-w[\s]+/etc/security/opasswd" /etc/audit/rules.d/*.rules)

# For each of the matched entries
for match in "${matches[@]}"
do
    # Extract filepath from the match
    rulesd_audit_file=$(echo $match | cut -f1 -d ':')
    # Append that path into list of files for inspection
    files_to_inspect+=("$rulesd_audit_file")
done
# Case when particular audit rule isn't defined yet
if [ "${#files_to_inspect[@]}" -eq "0" ]
then
    # Append '/etc/audit/rules.d/audit_rules_usergroup_modification.rules' into list of files for inspection
    key_rule_file="/etc/audit/rules.d/audit_rules_usergroup_modification.rules"
    # If the audit_rules_usergroup_modification.rules file doesn't exist yet, create it with correct permissions
    if [ ! -e "$key_rule_file" ]
    then
        touch "$key_rule_file"
        chmod 0640 "$key_rule_file"
    fi
    files_to_inspect+=("$key_rule_file")
fi

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "[\s]*-w[\s]+/etc/security/opasswd" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/security/opasswd $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/security/opasswd$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/security/opasswd -p wa -k audit_rules_usergroup_modification" >> "$audit_rules_file"
    fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_opasswd
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit opasswd tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_opasswd
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Search /etc/audit/rules.d for other user/group modification audit rules
  find:
    paths: /etc/audit/rules.d
    recurse: false
    contains: -k audit_rules_usergroup_modification$
    patterns: '*.rules'
  register: find_opasswd
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_opasswd
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: If existing user/group modification ruleset not found, use /etc/audit/rules.d/privileged.rules
    as the recipient for the rule
  set_fact:
    all_files:
      - /etc/audit/rules.d/privileged.rules
  when:
    - '"audit" in ansible_facts.packages'
    - find_opasswd.matched is defined and find_opasswd.matched == 0
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_opasswd
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Use matched file as the recipient for the rule
  set_fact:
    all_files:
      - '{{ find_opasswd.files | map(attribute=''path'') | list | first }}'
  when:
    - '"audit" in ansible_facts.packages'
    - find_opasswd.matched is defined and find_opasswd.matched > 0
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_opasswd
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Inserts/replaces the opasswd rule in rules.d when on x86
  lineinfile:
    path: '{{ all_files[0] }}'
    line: -w /etc/security/opasswd -p wa -k audit_rules_usergroup_modification
    create: true
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_opasswd
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Inserts/replaces the opasswd rule in /etc/audit/audit.rules
  lineinfile:
    line: -w /etc/security/opasswd -p wa -k audit_rules_usergroup_modification
    state: present
    dest: /etc/audit/audit.rules
    create: true
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_opasswd
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules opasswd  oval:ssg-test_audit_rules_usergroup_modification_opasswd_augen:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_usergroup_modification_opasswd_augen:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^\-w[\s]+\/etc\/security\/opasswd[\s]+\-p[\s]+\b([rx]*w[rx]*a[rx]*|[rx]*a[rx]*w[rx]*)\b[\s]+(-k[\s]+|-F[\s]+key=)\w+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit opasswd  oval:ssg-test_audit_rules_usergroup_modification_opasswd_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_usergroup_modification_opasswd_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^\-w[\s]+\/etc\/security\/opasswd[\s]+\-p[\s]+\b([rx]*w[rx]*a[rx]*|[rx]*a[rx]*w[rx]*)\b[\s]+(-k[\s]+|-F[\s]+key=)\w+[\s]*$1
Record Events that Modify User/Group Information - /etc/passwdxccdf_org.ssgproject.content_rule_audit_rules_usergroup_modification_passwd medium

Record Events that Modify User/Group Information - /etc/passwd

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_usergroup_modification_passwd
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_usergroup_modification_passwd:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 18, 19, 2, 3, 4, 5, 6, 7, 8, 9, 5.4.1.1, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, DSS06.03, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000018, CCI-000169, CCI-000172, CCI-001403, CCI-001404, CCI-001405, CCI-001683, CCI-001684, CCI-001685, CCI-001686, CCI-002130, CCI-002132, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.2.2, 4.3.3.3.9, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.8, 4.3.3.6.6, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.1, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.1.2, A.6.2.1, A.6.2.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.1, A.9.4.2, A.9.4.3, A.9.4.4, A.9.4.5, CIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3, AC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-1, PR.AC-3, PR.AC-4, PR.AC-6, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.2.5, SRG-OS-000004-GPOS-00004, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000304-GPOS-00121, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000470-GPOS-00214, SRG-OS-000471-GPOS-00215, SRG-OS-000239-GPOS-00089, SRG-OS-000240-GPOS-00090, SRG-OS-000241-GPOS-00091, SRG-OS-000303-GPOS-00120, SRG-OS-000304-GPOS-00121, SRG-OS-000466-GPOS-00210, SRG-OS-000476-GPOS-00221, SRG-OS-000274-GPOS-00104, SRG-OS-000275-GPOS-00105, SRG-OS-000276-GPOS-00106, SRG-OS-000277-GPOS-00107, SRG-OS-000004-VMM-000040, SRG-OS-000239-VMM-000810, SRG-OS-000240-VMM-000820, SRG-OS-000241-VMM-000830, SRG-OS-000274-VMM-000960, SRG-OS-000275-VMM-000970, SRG-OS-000276-VMM-000980, SRG-OS-000277-VMM-000990, SRG-OS-000303-VMM-001090, SRG-OS-000304-VMM-001100, SRG-OS-000476-VMM-001960

Description
If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d, in order to capture events that modify account changes:

-w /etc/passwd -p wa -k audit_rules_usergroup_modification


If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file, in order to capture events that modify account changes:

-w /etc/passwd -p wa -k audit_rules_usergroup_modification
Rationale
In addition to auditing new user and group accounts, these watches will alert the system administrator(s) to any modifications. Any unexpected users, groups, or modifications should be investigated for legitimacy.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()


# If the audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# into the list of files to be inspected
files_to_inspect+=('/etc/audit/audit.rules')

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "[\s]*-w[\s]+/etc/passwd" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/passwd $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/passwd$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/passwd -p wa -k audit_rules_usergroup_modification" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()

# If the audit is 'augenrules', then check if rule is already defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to list of files for inspection.
# If rule isn't defined, add '/etc/audit/rules.d/audit_rules_usergroup_modification.rules' to list of files for inspection.
readarray -t matches < <(grep -HP "[\s]*-w[\s]+/etc/passwd" /etc/audit/rules.d/*.rules)

# For each of the matched entries
for match in "${matches[@]}"
do
    # Extract filepath from the match
    rulesd_audit_file=$(echo $match | cut -f1 -d ':')
    # Append that path into list of files for inspection
    files_to_inspect+=("$rulesd_audit_file")
done
# Case when particular audit rule isn't defined yet
if [ "${#files_to_inspect[@]}" -eq "0" ]
then
    # Append '/etc/audit/rules.d/audit_rules_usergroup_modification.rules' into list of files for inspection
    key_rule_file="/etc/audit/rules.d/audit_rules_usergroup_modification.rules"
    # If the audit_rules_usergroup_modification.rules file doesn't exist yet, create it with correct permissions
    if [ ! -e "$key_rule_file" ]
    then
        touch "$key_rule_file"
        chmod 0640 "$key_rule_file"
    fi
    files_to_inspect+=("$key_rule_file")
fi

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "[\s]*-w[\s]+/etc/passwd" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/passwd $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/passwd$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/passwd -p wa -k audit_rules_usergroup_modification" >> "$audit_rules_file"
    fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_passwd
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit passwd tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_passwd
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Search /etc/audit/rules.d for other user/group modification audit rules
  find:
    paths: /etc/audit/rules.d
    recurse: false
    contains: -k audit_rules_usergroup_modification$
    patterns: '*.rules'
  register: find_passwd
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_passwd
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: If existing user/group modification ruleset not found, use /etc/audit/rules.d/privileged.rules
    as the recipient for the rule
  set_fact:
    all_files:
      - /etc/audit/rules.d/privileged.rules
  when:
    - '"audit" in ansible_facts.packages'
    - find_passwd.matched is defined and find_passwd.matched == 0
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_passwd
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Use matched file as the recipient for the rule
  set_fact:
    all_files:
      - '{{ find_passwd.files | map(attribute=''path'') | list | first }}'
  when:
    - '"audit" in ansible_facts.packages'
    - find_passwd.matched is defined and find_passwd.matched > 0
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_passwd
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Inserts/replaces the passwd rule in rules.d when on x86
  lineinfile:
    path: '{{ all_files[0] }}'
    line: -w /etc/passwd -p wa -k audit_rules_usergroup_modification
    create: true
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_passwd
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Inserts/replaces the passwd rule in /etc/audit/audit.rules
  lineinfile:
    line: -w /etc/passwd -p wa -k audit_rules_usergroup_modification
    state: present
    dest: /etc/audit/audit.rules
    create: true
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_passwd
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules passwd  oval:ssg-test_audit_rules_usergroup_modification_passwd_augen:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_usergroup_modification_passwd_augen:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^\-w[\s]+\/etc\/passwd[\s]+\-p[\s]+\b([rx]*w[rx]*a[rx]*|[rx]*a[rx]*w[rx]*)\b[\s]+(-k[\s]+|-F[\s]+key=)\w+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit passwd  oval:ssg-test_audit_rules_usergroup_modification_passwd_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_usergroup_modification_passwd_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^\-w[\s]+\/etc\/passwd[\s]+\-p[\s]+\b([rx]*w[rx]*a[rx]*|[rx]*a[rx]*w[rx]*)\b[\s]+(-k[\s]+|-F[\s]+key=)\w+[\s]*$1
Record Events that Modify User/Group Information - /etc/shadowxccdf_org.ssgproject.content_rule_audit_rules_usergroup_modification_shadow medium

Record Events that Modify User/Group Information - /etc/shadow

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_usergroup_modification_shadow
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-audit_rules_usergroup_modification_shadow:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 18, 19, 2, 3, 4, 5, 6, 7, 8, 9, 5.4.1.1, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, DSS06.03, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.1.7, CCI-000018, CCI-000169, CCI-000172, CCI-001403, CCI-001404, CCI-001405, CCI-001683, CCI-001684, CCI-001685, CCI-001686, CCI-002130, CCI-002132, 164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e), 4.2.3.10, 4.3.2.6.7, 4.3.3.2.2, 4.3.3.3.9, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.8, 4.3.3.6.6, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.1, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.1.2, A.6.2.1, A.6.2.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.1, A.9.4.2, A.9.4.3, A.9.4.4, A.9.4.5, CIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3, AC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a), DE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-1, PR.AC-3, PR.AC-4, PR.AC-6, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.2.5, SRG-OS-000004-GPOS-00004, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000304-GPOS-00121, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000470-GPOS-00214, SRG-OS-000471-GPOS-00215, SRG-OS-000239-GPOS-00089, SRG-OS-000240-GPOS-00090, SRG-OS-000241-GPOS-00091, SRG-OS-000303-GPOS-00120, SRG-OS-000304-GPOS-00121, SRG-OS-000466-GPOS-00210, SRG-OS-000476-GPOS-00221, SRG-OS-000004-VMM-000040, SRG-OS-000239-VMM-000810, SRG-OS-000240-VMM-000820, SRG-OS-000241-VMM-000830, SRG-OS-000274-VMM-000960, SRG-OS-000275-VMM-000970, SRG-OS-000276-VMM-000980, SRG-OS-000277-VMM-000990, SRG-OS-000303-VMM-001090, SRG-OS-000304-VMM-001100, SRG-OS-000476-VMM-001960

Description
If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d, in order to capture events that modify account changes:

-w /etc/shadow -p wa -k audit_rules_usergroup_modification


If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file, in order to capture events that modify account changes:

-w /etc/shadow -p wa -k audit_rules_usergroup_modification
Rationale
In addition to auditing new user and group accounts, these watches will alert the system administrator(s) to any modifications. Any unexpected users, groups, or modifications should be investigated for legitimacy.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()


# If the audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# into the list of files to be inspected
files_to_inspect+=('/etc/audit/audit.rules')

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "[\s]*-w[\s]+/etc/shadow" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/shadow $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/shadow$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/shadow -p wa -k audit_rules_usergroup_modification" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()

# If the audit is 'augenrules', then check if rule is already defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to list of files for inspection.
# If rule isn't defined, add '/etc/audit/rules.d/audit_rules_usergroup_modification.rules' to list of files for inspection.
readarray -t matches < <(grep -HP "[\s]*-w[\s]+/etc/shadow" /etc/audit/rules.d/*.rules)

# For each of the matched entries
for match in "${matches[@]}"
do
    # Extract filepath from the match
    rulesd_audit_file=$(echo $match | cut -f1 -d ':')
    # Append that path into list of files for inspection
    files_to_inspect+=("$rulesd_audit_file")
done
# Case when particular audit rule isn't defined yet
if [ "${#files_to_inspect[@]}" -eq "0" ]
then
    # Append '/etc/audit/rules.d/audit_rules_usergroup_modification.rules' into list of files for inspection
    key_rule_file="/etc/audit/rules.d/audit_rules_usergroup_modification.rules"
    # If the audit_rules_usergroup_modification.rules file doesn't exist yet, create it with correct permissions
    if [ ! -e "$key_rule_file" ]
    then
        touch "$key_rule_file"
        chmod 0640 "$key_rule_file"
    fi
    files_to_inspect+=("$key_rule_file")
fi

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "[\s]*-w[\s]+/etc/shadow" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/shadow $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/shadow$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/shadow -p wa -k audit_rules_usergroup_modification" >> "$audit_rules_file"
    fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_shadow
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Set architecture for audit shadow tasks
  set_fact:
    audit_arch: b{{ ansible_architecture | regex_replace('.*(\d\d$)','\1') }}
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_shadow
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Search /etc/audit/rules.d for other user/group modification audit rules
  find:
    paths: /etc/audit/rules.d
    recurse: false
    contains: -k audit_rules_usergroup_modification$
    patterns: '*.rules'
  register: find_shadow
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_shadow
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: If existing user/group modification ruleset not found, use /etc/audit/rules.d/privileged.rules
    as the recipient for the rule
  set_fact:
    all_files:
      - /etc/audit/rules.d/privileged.rules
  when:
    - '"audit" in ansible_facts.packages'
    - find_shadow.matched is defined and find_shadow.matched == 0
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_shadow
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Use matched file as the recipient for the rule
  set_fact:
    all_files:
      - '{{ find_shadow.files | map(attribute=''path'') | list | first }}'
  when:
    - '"audit" in ansible_facts.packages'
    - find_shadow.matched is defined and find_shadow.matched > 0
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_shadow
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Inserts/replaces the shadow rule in rules.d when on x86
  lineinfile:
    path: '{{ all_files[0] }}'
    line: -w /etc/shadow -p wa -k audit_rules_usergroup_modification
    create: true
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_shadow
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Inserts/replaces the shadow rule in /etc/audit/audit.rules
  lineinfile:
    line: -w /etc/shadow -p wa -k audit_rules_usergroup_modification
    state: present
    dest: /etc/audit/audit.rules
    create: true
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.1.7
    - NIST-800-53-AC-2(4)
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.2.5
    - audit_rules_usergroup_modification_shadow
    - low_complexity
    - low_disruption
    - medium_severity
    - reboot_required
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

audit augenrules shadow  oval:ssg-test_audit_rules_usergroup_modification_shadow_augen:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_usergroup_modification_shadow_augen:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/audit/rules\.d/.*\.rules$^\-w[\s]+\/etc\/shadow[\s]+\-p[\s]+\b([rx]*w[rx]*a[rx]*|[rx]*a[rx]*w[rx]*)\b[\s]+(-k[\s]+|-F[\s]+key=)\w+[\s]*$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

audit shadow  oval:ssg-test_audit_rules_usergroup_modification_shadow_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_usergroup_modification_shadow_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audit.rules^\-w[\s]+\/etc\/shadow[\s]+\-p[\s]+\b([rx]*w[rx]*a[rx]*|[rx]*a[rx]*w[rx]*)\b[\s]+(-k[\s]+|-F[\s]+key=)\w+[\s]*$1
Record Access Events to Audit Log Directoryxccdf_org.ssgproject.content_rule_directory_access_var_log_audit medium

Record Access Events to Audit Log Directory

Rule IDxccdf_org.ssgproject.content_rule_directory_access_var_log_audit
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-directory_access_var_log_audit:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  AU-2(d), AU-12(c), AC-6(9), CM-6(a), FAU_GEN.1.1.c

Description
The audit system should collect access events to read audit log directory. The following audit rule will assure that access to audit log directory are collected.
-a always,exit -F dir=/var/log/audit/ -F perm=r -F auid>=1000 -F auid!=unset -F key=access-audit-trail
If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the rule to a file with suffix .rules in the directory /etc/audit/rules.d. If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the rule to /etc/audit/audit.rules file.
Rationale
Attempts to read the logs should be recorded, suspicious access to audit log files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.'

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit && { [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; }; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F dir=/var/log/audit/ -F perm=r"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="access-audit-trail"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
# 
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()



# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - directory_access_var_log_audit
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Perform remediation of Audit rules for /var/log/audit
  block:

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/rules.d/
      find:
        paths: /etc/audit/rules.d
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F dir=/var/log/audit/ -F perm=r -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: '*.rules'
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Reset syscalls found per file
      set_fact:
        syscalls_per_file: {}
        found_paths_dict: {}

    - name: Declare syscalls found per file
      set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
        :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
      loop: '{{ find_command.results | selectattr(''matched'') | list }}'

    - name: Declare files where syscalls were found
      set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
        | map(attribute='path') | list }}"

    - name: Count occurrences of syscalls in paths
      set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
        0) }) }}"
      loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
        | list }}'

    - name: Get path with most syscalls
      set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
        | last).key }}"
      when: found_paths | length >= 1

    - name: No file with syscall found, set path to /etc/audit/rules.d/access-audit-trail.rules
      set_fact: audit_file="/etc/audit/rules.d/access-audit-trail.rules"
      when: found_paths | length == 0

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
          | join("|") }}))\b)((?:( -S |,)\w+)+)( -F dir=/var/log/audit/ -F perm=r
          -F auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F dir=/var/log/audit/ -F perm=r
          -F auid>=1000 -F auid!=unset -F key=access-audit-trail
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0

    - name: Declare list of syscalls
      set_fact:
        syscalls: []
        syscall_grouping: []

    - name: Check existence of  in /etc/audit/audit.rules
      find:
        paths: /etc/audit
        contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)*
          -F dir=/var/log/audit/ -F perm=r -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
        patterns: audit.rules
      register: find_command
      loop: '{{ (syscall_grouping + syscalls) | unique }}'

    - name: Set path to /etc/audit/audit.rules
      set_fact: audit_file="/etc/audit/audit.rules"

    - name: Declare found syscalls
      set_fact: syscalls_found="{{ find_command.results | selectattr('matched') |
        map(attribute='item') | list }}"

    - name: Declare missing syscalls
      set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

    - name: Replace the audit rule in {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|")
          }}))\b)((?:( -S |,)\w+)+)( -F dir=/var/log/audit/ -F perm=r -F auid>=1000
          -F auid!=unset (?:-k |-F key=)\w+)
        line: \1\2\3{{ missing_syscalls | join("\3") }}\4
        backrefs: true
        state: present
      when: syscalls_found | length > 0 and missing_syscalls | length > 0

    - name: Add the audit rule to {{ audit_file }}
      lineinfile:
        path: '{{ audit_file }}'
        line: -a always,exit{{ syscalls | join(',') }} -F dir=/var/log/audit/ -F perm=r
          -F auid>=1000 -F auid!=unset -F key=access-audit-trail
        create: true
        mode: o-rwx
        state: present
      when: syscalls_found | length == 0
  when:
    - '"audit" in ansible_facts.packages'
    - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-AC-6(9)
    - NIST-800-53-AU-12(c)
    - NIST-800-53-AU-2(d)
    - NIST-800-53-CM-6(a)
    - directory_access_var_log_audit
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
OVAL test results details

audit augenrules  oval:ssg-test_audit_rules_augenrules:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/systemd/system/auditd.serviceExecStartPost=-/sbin/augenrules --load

defined audit rule must exist  oval:ssg-test_directory_acccess_var_log_audit_augenrules:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_directory_acccess_var_log_audit_augenrules:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+dir=/var/log/audit/)[\s]+(?:-F[\s]+perm=r)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$^/etc/audit/rules\.d/.*\.rules$1

audit auditctl  oval:ssg-test_audit_rules_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_audit_rules_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/usr/lib/systemd/system/auditd.service^ExecStartPost=\-\/sbin\/auditctl.*$1

defined audit rule must exist  oval:ssg-test_directory_acccess_var_log_audit_auditctl:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_directory_acccess_var_log_audit_auditctl:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^[\s]*-a[\s]+always,exit[\s]+(?:-F[\s]+dir=/var/log/audit/)[\s]+(?:-F[\s]+perm=r)[\s]+(?:-F\s+auid>=1000[\s]+)(?:-F\s+auid!=(unset|4294967295)[\s]+)(?:-k[\s]+|-F[\s]+key=)[\S]+[\s]*$/etc/audit/audit.rules1
Configure audispd Plugin To Send Logs To Remote Serverxccdf_org.ssgproject.content_rule_auditd_audispd_configure_remote_server medium

Configure audispd Plugin To Send Logs To Remote Server

Rule IDxccdf_org.ssgproject.content_rule_auditd_audispd_configure_remote_server
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-auditd_audispd_configure_remote_server:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-001851, FAU_GEN.1.1.c, SRG-OS-000342-GPOS-00133, SRG-OS-000479-GPOS-00224, SRG-OS-000051-VMM-000230, SRG-OS-000058-VMM-000270, SRG-OS-000059-VMM-000280, SRG-OS-000479-VMM-001990, SRG-OS-000479-VMM-001990

Description
Configure the audispd plugin to off-load audit records onto a different system or media from the system being audited. Set the remote_server option in
/etc/audit/audisp-remote.conf
with an IP address or hostname of the system that the audispd plugin should send audit records to. For example
remote_server = logcollector
Rationale
Information stored in one location is vulnerable to accidental or incidental deletion or alteration.Off-loading is a common process in information systems with limited audit storage capacity.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

var_audispd_remote_server='logcollector'



AUDITCONFIG=/etc/audit/audisp-remote.conf




# Test if the config_file is a symbolic link. If so, use --follow-symlinks with sed.
# Otherwise, regular sed command will do.
sed_command=('sed' '-i')
if test -L "$AUDITCONFIG"; then
    sed_command+=('--follow-symlinks')
fi

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^remote_server")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "$var_audispd_remote_server"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^remote_server\\>" "$AUDITCONFIG"; then
    "${sed_command[@]}" "s/^remote_server\\>.*/$formatted_output/gi" "$AUDITCONFIG"
else
    # \n is precaution for case where file ends without trailing newline
    
    printf '%s\n' "$formatted_output" >> "$AUDITCONFIG"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - auditd_audispd_configure_remote_server
    - configure_strategy
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
- name: XCCDF Value var_audispd_remote_server # promote to variable
  set_fact:
    var_audispd_remote_server: !!str logcollector
  tags:
    - always

- name: Make sure that a remote server is configured for Audispd
  lineinfile:
    path: /etc/audit/audisp-remote.conf
    line: remote_server = {{ var_audispd_remote_server }}
    regexp: ^\s*remote_server\s*=.*$
    create: true
    state: present
  when: '"audit" in ansible_facts.packages'
  tags:
    - auditd_audispd_configure_remote_server
    - configure_strategy
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
OVAL test results details

remote server to send audit records  oval:ssg-test_auditd_audispd_configure_remote_server:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_auditd_audispd_configure_remote_server:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audisp-remote.conf^[ ]*remote_server[ ]+=[ ]+(\S+)[ ]*$1
Encrypt Audit Records Sent With audispd Pluginxccdf_org.ssgproject.content_rule_auditd_audispd_encrypt_sent_records medium

Encrypt Audit Records Sent With audispd Plugin

Rule IDxccdf_org.ssgproject.content_rule_auditd_audispd_encrypt_sent_records
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-auditd_audispd_encrypt_sent_records:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-001851, AU-9(3), CM-6(a), FAU_GEN.1.1.c, SRG-OS-000342-GPOS-00133, SRG-OS-000479-GPOS-00224

Description
Configure the operating system to encrypt the transfer of off-loaded audit records onto a different system or media from the system being audited. Set the transport option in
/etc/audit/audisp-remote.conf
to KRB5.
Rationale
Information stored in one location is vulnerable to accidental or incidental deletion or alteration. Off-loading is a common process in information systems with limited audit storage capacity.

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

AUDISP_REMOTE_CONFIG="/etc/audit/audisp-remote.conf"
option="^transport"
value="KRB5"


# Test if the config_file is a symbolic link. If so, use --follow-symlinks with sed.
# Otherwise, regular sed command will do.
sed_command=('sed' '-i')
if test -L "$AUDISP_REMOTE_CONFIG"; then
    sed_command+=('--follow-symlinks')
fi

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "$option")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "$value"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "$option\\>" "$AUDISP_REMOTE_CONFIG"; then
    "${sed_command[@]}" "s/$option\\>.*/$formatted_output/gi" "$AUDISP_REMOTE_CONFIG"
else
    # \n is precaution for case where file ends without trailing newline
    
    printf '%s\n' "$formatted_output" >> "$AUDISP_REMOTE_CONFIG"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
OVAL test results details

setting in audisp-remote.conf  oval:ssg-test_auditd_audispd_encrypt_sent_records:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_auditd_audispd_encrypt_sent_records:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/audisp-remote.conf^[ ]*transport[ ]+=[ ]+KRB5[ ]*$1
Configure auditd to use audispd's syslog pluginxccdf_org.ssgproject.content_rule_auditd_audispd_syslog_plugin_activated medium

Configure auditd to use audispd's syslog plugin

Rule IDxccdf_org.ssgproject.content_rule_auditd_audispd_syslog_plugin_activated
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-auditd_audispd_syslog_plugin_activated:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 3, 4, 5, 6, 7, 8, 5.4.1.1, APO11.04, APO12.06, BAI03.05, BAI08.02, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS05.04, DSS05.07, MEA02.01, 3.3.1, CCI-000136, 164.308(a)(1)(ii)(D), 164.308(a)(5)(ii)(B), 164.308(a)(5)(ii)(C), 164.308(a)(6)(ii), 164.308(a)(8), 164.310(d)(2)(iii), 164.312(b), 164.314(a)(2)(i)(C), 164.314(a)(2)(iii), 4.2.3.10, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.16.1.4, A.16.1.5, A.16.1.7, AU-4(1), CM-6(a), DE.AE-3, DE.AE-5, PR.PT-1, RS.AN-1, RS.AN-4, FAU_GEN.1.1.c, Req-10.5.3, SRG-OS-000479-GPOS-00224, SRG-OS-000342-GPOS-00133, SRG-OS-000051-VMM-000230, SRG-OS-000058-VMM-000270, SRG-OS-000059-VMM-000280, SRG-OS-000479-VMM-001990, SRG-OS-000479-VMM-001990

Description
To configure the auditd service to use the syslog plug-in of the audispd audit event multiplexor, set the active line in /etc/audit/plugins.d/syslog.conf to yes. Restart the auditd service:
$ sudo service auditd restart
Rationale
The auditd service does not include the ability to send audit records to a centralized server for management directly. It does, however, include a plug-in for audit event multiplexor (audispd) to pass audit records to the local syslog server

# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

var_syslog_active="yes"


AUDISP_SYSLOGCONFIG=/etc/audit/plugins.d/syslog.conf


# Test if the config_file is a symbolic link. If so, use --follow-symlinks with sed.
# Otherwise, regular sed command will do.
sed_command=('sed' '-i')
if test -L "$AUDISP_SYSLOGCONFIG"; then
    sed_command+=('--follow-symlinks')
fi

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^active")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "$var_syslog_active"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^active\\>" "$AUDISP_SYSLOGCONFIG"; then
    "${sed_command[@]}" "s/^active\\>.*/$formatted_output/gi" "$AUDISP_SYSLOGCONFIG"
else
    # \n is precaution for case where file ends without trailing newline
    
    printf '%s\n' "$formatted_output" >> "$AUDISP_SYSLOGCONFIG"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.3.1
    - NIST-800-53-AU-4(1)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.3
    - auditd_audispd_syslog_plugin_activated
    - configure_strategy
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed

- name: enable syslog plugin
  lineinfile:
    dest: /etc/audit/plugins.d/syslog.conf
    regexp: ^active
    line: active = yes
    create: true
  when: '"audit" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.3.1
    - NIST-800-53-AU-4(1)
    - NIST-800-53-CM-6(a)
    - PCI-DSS-Req-10.5.3
    - auditd_audispd_syslog_plugin_activated
    - configure_strategy
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
OVAL test results details

audispd syslog plugin activated  oval:ssg-test_auditd_audispd_syslog_plugin_activated:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_auditd_audispd_syslog_plugin_activated:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/audit/plugins.d/syslog.conf^[ ]*active[ ]+=[ ]+yes[ ]*$1
Set number of records to cause an explicit flush to audit logsxccdf_org.ssgproject.content_rule_auditd_freq medium

Set number of records to cause an explicit flush to audit logs

Rule IDxccdf_org.ssgproject.content_rule_auditd_freq
Result
pass
Multi-check ruleno
OVAL Definition IDoval:ssg-auditd_freq:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CM-6, FAU_GEN.1, SRG-OS-000051-GPOS-00024

Description
To configure Audit daemon to issue an explicit flush to disk command after writing 50 records, set freq to 50 in /etc/audit/auditd.conf.
Rationale
If option freq isn't set to 50, the flush to disk may happen after higher number of records, increasing the danger of audit loss.
OVAL test results details

tests the value of freq setting in the /etc/audit/auditd.conf file  oval:ssg-test_auditd_freq:tst:1  true

Following items have been found on the system:
PathContent
/etc/audit/auditd.conffreq = 50
Include Local Events in Audit Logsxccdf_org.ssgproject.content_rule_auditd_local_events medium

Include Local Events in Audit Logs

Rule IDxccdf_org.ssgproject.content_rule_auditd_local_events
Result
pass
Multi-check ruleno
OVAL Definition IDoval:ssg-auditd_local_events:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-000366, CM-6, FAU_GEN.1, SRG-OS-000062-GPOS-00031, SRG-OS-000480-GPOS-00227

Description
To configure Audit daemon to include local events in Audit logs, set local_events to yes in /etc/audit/auditd.conf. This is the default setting.
Rationale
If option local_events isn't set to yes only events from network will be aggregated.
OVAL test results details

tests the value of local_events setting in the /etc/audit/auditd.conf file  oval:ssg-test_auditd_local_events:tst:1  true

Following items have been found on the system:
PathContent
/etc/audit/auditd.conflocal_events = yes

tests the absence of local_events setting in the /etc/audit/auditd.conf file  oval:ssg-test_auditd_local_events_default_not_overriden:tst:1  false

Following items have been found on the system:
PathContent
/etc/audit/auditd.conflocal_events =
Resolve information before writing to audit logsxccdf_org.ssgproject.content_rule_auditd_log_format medium

Resolve information before writing to audit logs

Rule IDxccdf_org.ssgproject.content_rule_auditd_log_format
Result
pass
Multi-check ruleno
OVAL Definition IDoval:ssg-auditd_log_format:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-000366, CM-6, AU-3, FAU_GEN.1.2, SRG-OS-000255-GPOS-00096, SRG-OS-000480-GPOS-00227

Description
To configure Audit daemon to resolve all uid, gid, syscall, architecture, and socket address information before writing the events to disk, set log_format to ENRICHED in /etc/audit/auditd.conf.
Rationale
If option log_format isn't set to ENRICHED, the audit records will be stored in a format exactly as the kernel sends them.
OVAL test results details

tests the value of log_format setting in the /etc/audit/auditd.conf file  oval:ssg-test_auditd_log_format:tst:1  true

Following items have been found on the system:
PathContent
/etc/audit/auditd.conflog_format = ENRICHED
Set hostname as computer node name in audit logsxccdf_org.ssgproject.content_rule_auditd_name_format medium

Set hostname as computer node name in audit logs

Rule IDxccdf_org.ssgproject.content_rule_auditd_name_format
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-auditd_name_format:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-001851, CM-6, AU-3, FAU_GEN.1.2, SRG-OS-000039-GPOS-00017, SRG-OS-000342-GPOS-00133, SRG-OS-000479-GPOS-00224

Description
To configure Audit daemon to use value returned by gethostname syscall as computer node name in the audit events, set name_format to hostname in /etc/audit/auditd.conf.
Rationale
If option name_format is left at its default value of none, audit events from different computers may be hard to distinguish.

Complexity:low
Disruption:low
Strategy:restrict
# Remediation is applicable only in certain platforms
if rpm --quiet -q audit; then

if [ -e "/etc/audit/auditd.conf" ] ; then
    
    LC_ALL=C sed -i "/^\s*name_format\s*=\s*/Id" "/etc/audit/auditd.conf"
else
    touch "/etc/audit/auditd.conf"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/audit/auditd.conf"

cp "/etc/audit/auditd.conf" "/etc/audit/auditd.conf.bak"
# Insert at the end of the file
printf '%s\n' "name_format = hostname" >> "/etc/audit/auditd.conf"
# Clean up after ourselves.
rm "/etc/audit/auditd.conf.bak"

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-AU-3
    - NIST-800-53-CM-6
    - auditd_name_format
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

- name: Set hostname as computer node name in audit logs
  block:

    - name: Check for duplicate values
      lineinfile:
        path: /etc/audit/auditd.conf
        create: false
        regexp: (?i)^\s*name_format\s*=\s*
        state: absent
      check_mode: true
      changed_when: false
      register: dupes

    - name: Deduplicate values from /etc/audit/auditd.conf
      lineinfile:
        path: /etc/audit/auditd.conf
        create: false
        regexp: (?i)^\s*name_format\s*=\s*
        state: absent
      when: dupes.found is defined and dupes.found > 1

    - name: Insert correct line to /etc/audit/auditd.conf
      lineinfile:
        path: /etc/audit/auditd.conf
        create: true
        regexp: (?i)^\s*name_format\s*=\s*
        line: name_format = hostname
        state: present
  when: '"audit" in ansible_facts.packages'
  tags:
    - NIST-800-53-AU-3
    - NIST-800-53-CM-6
    - auditd_name_format
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,{{ %23%0A%23%20This%20file%20controls%20the%20configuration%20of%20the%20audit%20daemon%0A%23%0A%0Alocal_events%20%3D%20yes%0Awrite_logs%20%3D%20yes%0Alog_file%20%3D%20/var/log/audit/audit.log%0Alog_group%20%3D%20root%0Alog_format%20%3D%20ENRICHED%0Aflush%20%3D%20%7B%7B.var_auditd_flush%7D%7D%0Afreq%20%3D%2050%0Amax_log_file%20%3D%20%7B%7B.var_auditd_max_log_file%7D%7D%0Anum_logs%20%3D%20%7B%7B.var_auditd_num_logs%7D%7D%0Apriority_boost%20%3D%204%0Aname_format%20%3D%20hostname%0A%23%23name%20%3D%20mydomain%0Amax_log_file_action%20%3D%20%7B%7B.var_auditd_max_log_file_action%7D%7D%0Aspace_left%20%3D%20%7B%7B.var_auditd_space_left%7D%7D%0Aspace_left_action%20%3D%20%7B%7B.var_auditd_space_left_action%7D%7D%0Averify_email%20%3D%20yes%0Aaction_mail_acct%20%3D%20%7B%7B.var_auditd_action_mail_acct%7D%7D%0Aadmin_space_left%20%3D%2050%0Aadmin_space_left_action%20%3D%20syslog%0Adisk_full_action%20%3D%20%7B%7B.var_auditd_disk_full_action%7D%7D%0Adisk_error_action%20%3D%20%7B%7B.var_auditd_disk_error_action%7D%7D%0Ause_libwrap%20%3D%20yes%0A%23%23tcp_listen_port%20%3D%2060%0Atcp_listen_queue%20%3D%205%0Atcp_max_per_addr%20%3D%201%0A%23%23tcp_client_ports%20%3D%201024-65535%0Atcp_client_max_idle%20%3D%200%0Atransport%20%3D%20TCP%0Akrb5_principal%20%3D%20auditd%0A%23%23krb5_key_file%20%3D%20/etc/audit/audit.key%0Adistribute_network%20%3D%20no%0Aq_depth%20%3D%20400%0Aoverflow_action%20%3D%20syslog%0Amax_restarts%20%3D%2010%0Aplugin_dir%20%3D%20/etc/audit/plugins.d }}
        mode: 0640
        path: /etc/audit/auditd.conf
        overwrite: true
OVAL test results details

tests the value of name_format setting in the /etc/audit/auditd.conf file  oval:ssg-test_auditd_name_format:tst:1  false

Following items have been found on the system:
PathContent
/etc/audit/auditd.confname_format = NONE
Write Audit Logs to the Diskxccdf_org.ssgproject.content_rule_auditd_write_logs medium

Write Audit Logs to the Disk

Rule IDxccdf_org.ssgproject.content_rule_auditd_write_logs
Result
pass
Multi-check ruleno
OVAL Definition IDoval:ssg-auditd_write_logs:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CM-6, FAU_STG.1, SRG-OS-000480-GPOS-00227

Description
To configure Audit daemon to write Audit logs to the disk, set write_logs to yes in /etc/audit/auditd.conf. This is the default setting.
Rationale
If write_logs isn't set to yes, the Audit logs will not be written to the disk.
OVAL test results details

tests the value of write_logs setting in the /etc/audit/auditd.conf file  oval:ssg-test_auditd_write_logs:tst:1  true

Following items have been found on the system:
PathContent
/etc/audit/auditd.confwrite_logs = yes

tests the absence of write_logs setting in the /etc/audit/auditd.conf file  oval:ssg-test_auditd_write_logs_default_not_overriden:tst:1  false

Following items have been found on the system:
PathContent
/etc/audit/auditd.confwrite_logs =
Enable Auditing for Processes Which Start Prior to the Audit Daemonxccdf_org.ssgproject.content_rule_grub2_audit_argument medium

Enable Auditing for Processes Which Start Prior to the Audit Daemon

Rule IDxccdf_org.ssgproject.content_rule_grub2_audit_argument
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-grub2_audit_argument:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 19, 3, 4, 5, 6, 7, 8, 5.4.1.1, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS05.02, DSS05.03, DSS05.04, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, 3.3.1, CCI-001464, CCI-000130, CCI-000169, 164.308(a)(1)(ii)(D), 164.308(a)(5)(ii)(C), 164.310(a)(2)(iv), 164.310(d)(2)(iii), 164.312(b), 4.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 7.1, SR 7.6, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2, AC-17(1), AU-14(1), AU-10, CM-6(a), IR-5(1), DE.AE-3, DE.AE-5, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4, FAU_GEN.1, Req-10.3, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000473-GPOS-00218, SRG-OS-000254-GPOS-00095, SRG-OS-000254-VMM-000880

Description
To ensure all processes can be audited, even those which start prior to the audit daemon, add the argument audit=1 to the default GRUB 2 command line for the Linux operating system. Configure the default Grub2 kernel command line to contain audit=1 as follows:
# grub2-editenv - set "$(grub2-editenv - list | grep kernelopts) audit=1"
Rationale
Each process on the system carries an "auditable" flag which indicates whether its activities can be audited. Although auditd takes care of enabling this for all processes which launch after it does, adding the kernel argument ensures it is set for every process during boot.

# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && { rpm --quiet -q grub2-common; }; then

grubby --update-kernel=ALL --args=audit=1

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:medium
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.3.1
    - NIST-800-53-AC-17(1)
    - NIST-800-53-AU-10
    - NIST-800-53-AU-14(1)
    - NIST-800-53-CM-6(a)
    - NIST-800-53-IR-5(1)
    - PCI-DSS-Req-10.3
    - grub2_audit_argument
    - low_disruption
    - medium_complexity
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Update grub defaults and the bootloader menu
  command: /sbin/grubby --update-kernel=ALL --args="audit=1"
  when:
    - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
    - '"grub2-common" in ansible_facts.packages'
  tags:
    - CJIS-5.4.1.1
    - NIST-800-171-3.3.1
    - NIST-800-53-AC-17(1)
    - NIST-800-53-AU-10
    - NIST-800-53-AU-14(1)
    - NIST-800-53-CM-6(a)
    - NIST-800-53-IR-5(1)
    - PCI-DSS-Req-10.3
    - grub2_audit_argument
    - low_disruption
    - medium_complexity
    - medium_severity
    - reboot_required
    - restrict_strategy

[customizations.kernel]
append = "audit=1"
OVAL test results details

check for audit=1 in /etc/default/grub via GRUB_CMDLINE_LINUX  oval:ssg-test_grub2_audit_argument:tst:1  false

Following items have been found on the system:
PathContent
/etc/default/grubGRUB_CMDLINE_LINUX="rd.lvm.lv=fedora_fedora/root rhgb quiet"

check for audit=1 in /etc/default/grub via GRUB_CMDLINE_LINUX_DEFAULT  oval:ssg-test_grub2_audit_argument_default:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_grub2_audit_argument_default:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/default/grub^\s*GRUB_CMDLINE_LINUX_DEFAULT="(.*)"$1

Check for GRUB_DISABLE_RECOVERY=true in /etc/default/grub  oval:ssg-test_bootloader_disable_recovery_set_to_true:tst:1  true

Following items have been found on the system:
PathContent
/etc/default/grubGRUB_DISABLE_RECOVERY="true"
Extend Audit Backlog Limit for the Audit Daemonxccdf_org.ssgproject.content_rule_grub2_audit_backlog_limit_argument low

Extend Audit Backlog Limit for the Audit Daemon

Rule IDxccdf_org.ssgproject.content_rule_grub2_audit_backlog_limit_argument
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-grub2_audit_backlog_limit_argument:def:1
Time2024-12-29T17:33:55+01:00
Severitylow
Identifiers and References

References:  CCI-001849, CM-6(a), FAU_STG.1, FAU_STG.3, SRG-OS-000254-GPOS-00095, SRG-OS-000341-GPOS-00132

Description
To improve the kernel capacity to queue all log events, even those which occurred prior to the audit daemon, add the argument audit_backlog_limit=8192 to the default GRUB 2 command line for the Linux operating system. Configure the default Grub2 kernel command line to contain audit_backlog_limit=8192 as follows:
# grub2-editenv - set "$(grub2-editenv - list | grep kernelopts) audit_backlog_limit=8192"
Rationale
audit_backlog_limit sets the queue length for audit events awaiting transfer to the audit daemon. Until the audit daemon is up and running, all log messages are stored in this queue. If the queue is overrun during boot process, the action defined by audit failure flag is taken.

# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && { rpm --quiet -q grub2-common; }; then

grubby --update-kernel=ALL --args=audit_backlog_limit=8192

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:medium
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-CM-6(a)
    - grub2_audit_backlog_limit_argument
    - low_disruption
    - low_severity
    - medium_complexity
    - reboot_required
    - restrict_strategy

- name: Update grub defaults and the bootloader menu
  command: /sbin/grubby --update-kernel=ALL --args="audit_backlog_limit=8192"
  when:
    - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
    - '"grub2-common" in ansible_facts.packages'
  tags:
    - NIST-800-53-CM-6(a)
    - grub2_audit_backlog_limit_argument
    - low_disruption
    - low_severity
    - medium_complexity
    - reboot_required
    - restrict_strategy

[customizations.kernel]
append = "audit_backlog_limit=8192"
OVAL test results details

check for audit_backlog_limit=8192 in /etc/default/grub via GRUB_CMDLINE_LINUX  oval:ssg-test_grub2_audit_backlog_limit_argument:tst:1  false

Following items have been found on the system:
PathContent
/etc/default/grubGRUB_CMDLINE_LINUX="rd.lvm.lv=fedora_fedora/root rhgb quiet"

check for audit_backlog_limit=8192 in /etc/default/grub via GRUB_CMDLINE_LINUX_DEFAULT  oval:ssg-test_grub2_audit_backlog_limit_argument_default:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_grub2_audit_backlog_limit_argument_default:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/default/grub^\s*GRUB_CMDLINE_LINUX_DEFAULT="(.*)"$1

Check for GRUB_DISABLE_RECOVERY=true in /etc/default/grub  oval:ssg-test_bootloader_disable_recovery_set_to_true:tst:1  true

Following items have been found on the system:
PathContent
/etc/default/grubGRUB_DISABLE_RECOVERY="true"
Set Boot Loader Password in grub2xccdf_org.ssgproject.content_rule_grub2_password high

Set Boot Loader Password in grub2

Rule IDxccdf_org.ssgproject.content_rule_grub2_password
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-grub2_password:def:1
Time2024-12-29T17:33:55+01:00
Severityhigh
Identifiers and References

References:  BP28(R17), 1, 11, 12, 14, 15, 16, 18, 3, 5, DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.06, DSS06.10, 3.4.5, CCI-000213, 164.308(a)(1)(ii)(B), 164.308(a)(7)(i), 164.308(a)(7)(ii)(A), 164.310(a)(1), 164.310(a)(2)(i), 164.310(a)(2)(ii), 164.310(a)(2)(iii), 164.310(b), 164.310(c), 164.310(d)(1), 164.310(d)(2)(iii), 4.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, A.18.1.4, A.6.1.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.1, A.9.4.2, A.9.4.3, A.9.4.4, A.9.4.5, CM-6(a), PR.AC-1, PR.AC-4, PR.AC-6, PR.AC-7, PR.PT-3, FIA_UAU.1, SRG-OS-000080-GPOS-00048

Description
The grub2 boot loader should have a superuser account and password protection enabled to protect boot-time settings.

Since plaintext passwords are a security risk, generate a hash for the password by running the following command:
# grub2-setpassword
When prompted, enter the password that was selected.

Rationale
Password protection on the boot loader configuration ensures users with physical access cannot trivially alter important bootloader settings. These include which kernel to use, and whether to enter single-user mode.
Warnings
warning  To prevent hard-coded passwords, automatic remediation of this control is not available. Remediation must be automated as a component of machine provisioning, or followed manually as outlined above. Also, do NOT manually add the superuser account and password to the grub.cfg file as the grub2-mkconfig command overwrites this file.
OVAL test results details

Check if /boot/grub2/grub.cfg does not exist  oval:ssg-test_grub2_password_file_boot_grub2_grub_cfg_absent:tst:1  false

Following items have been found on the system:
PathTypeUIDGIDSize (B)Permissions
/boot/grub2/grub.cfgregular006754rw-r--r-- 

make sure a password is defined in /boot/grub2/user.cfg  oval:ssg-test_grub2_password_usercfg:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_grub2_password_usercfg:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/boot/grub2/user.cfg^[\s]*GRUB2_PASSWORD=grub\.pbkdf2\.sha512.*$1

make sure a password is defined in /boot/grub2/grub.cfg  oval:ssg-test_grub2_password_grubcfg:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_grub2_password_grubcfg:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/boot/grub2/grub.cfg^[\s]*password_pbkdf2[\s]+.*[\s]+grub\.pbkdf2\.sha512.*$1

superuser is defined in /boot/grub2/grub.cfg files.  oval:ssg-test_bootloader_superuser:tst:1  true

Following items have been found on the system:
PathContent
/boot/grub2/grub.cfg set superusers="root"
Set the UEFI Boot Loader Passwordxccdf_org.ssgproject.content_rule_grub2_uefi_password high

Set the UEFI Boot Loader Password

Rule IDxccdf_org.ssgproject.content_rule_grub2_uefi_password
Result
notapplicable
Multi-check ruleno
Time2024-12-29T17:33:55+01:00
Severityhigh
Identifiers and References

References:  BP28(R17), 11, 12, 14, 15, 16, 18, 3, 5, DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS06.03, DSS06.06, 3.4.5, CCI-000213, 164.308(a)(1)(ii)(B), 164.308(a)(7)(i), 164.308(a)(7)(ii)(A), 164.310(a)(1), 164.310(a)(2)(i), 164.310(a)(2)(ii), 164.310(a)(2)(iii), 164.310(b), 164.310(c), 164.310(d)(1), 164.310(d)(2)(iii), 4.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, A.6.1.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5, CM-6(a), PR.AC-4, PR.AC-6, PR.PT-3, FIA_UAU.1, SRG-OS-000080-GPOS-00048

Description
The grub2 boot loader should have a superuser account and password protection enabled to protect boot-time settings.

Since plaintext passwords are a security risk, generate a hash for the password by running the following command:
# grub2-setpassword
When prompted, enter the password that was selected.

Rationale
Password protection on the boot loader configuration ensures users with physical access cannot trivially alter important bootloader settings. These include which kernel to use, and whether to enter single-user mode.
Warnings
warning  To prevent hard-coded passwords, automatic remediation of this control is not available. Remediation must be automated as a component of machine provisioning, or followed manually as outlined above. Also, do NOT manually add the superuser account and password to the grub.cfg file as the grub2-mkconfig command overwrites this file.
Enable Kernel Page-Table Isolation (KPTI)xccdf_org.ssgproject.content_rule_grub2_pti_argument low

Enable Kernel Page-Table Isolation (KPTI)

Rule IDxccdf_org.ssgproject.content_rule_grub2_pti_argument
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-grub2_pti_argument:def:1
Time2024-12-29T17:33:55+01:00
Severitylow
Identifiers and References

References:  CCI-000381, SI-16, SRG-OS-000433-GPOS-00193, SRG-OS-000095-GPOS-00049

Description
To enable Kernel page-table isolation, add the argument pti=on to the default GRUB 2 command line for the Linux operating system. Configure the default Grub2 kernel command line to contain pti=on as follows:
# grub2-editenv - set "$(grub2-editenv - list | grep kernelopts) pti=on"
Rationale
Kernel page-table isolation is a kernel feature that mitigates the Meltdown security vulnerability and hardens the kernel against attempts to bypass kernel address space layout randomization (KASLR).

# Remediation is applicable only in certain platforms
if rpm --quiet -q grub2-common && { [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; }; then

grubby --update-kernel=ALL --args=pti=on

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:medium
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-SI-16
    - grub2_pti_argument
    - low_disruption
    - low_severity
    - medium_complexity
    - reboot_required
    - restrict_strategy

- name: Update grub defaults and the bootloader menu
  command: /sbin/grubby --update-kernel=ALL --args="pti=on"
  when:
    - '"grub2-common" in ansible_facts.packages'
    - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-SI-16
    - grub2_pti_argument
    - low_disruption
    - low_severity
    - medium_complexity
    - reboot_required
    - restrict_strategy

[customizations.kernel]
append = "pti=on"
OVAL test results details

check for pti=on in /etc/default/grub via GRUB_CMDLINE_LINUX  oval:ssg-test_grub2_pti_argument:tst:1  false

Following items have been found on the system:
PathContent
/etc/default/grubGRUB_CMDLINE_LINUX="rd.lvm.lv=fedora_fedora/root rhgb quiet"

check for pti=on in /etc/default/grub via GRUB_CMDLINE_LINUX_DEFAULT  oval:ssg-test_grub2_pti_argument_default:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_grub2_pti_argument_default:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/default/grub^\s*GRUB_CMDLINE_LINUX_DEFAULT="(.*)"$1

Check for GRUB_DISABLE_RECOVERY=true in /etc/default/grub  oval:ssg-test_bootloader_disable_recovery_set_to_true:tst:1  true

Following items have been found on the system:
PathContent
/etc/default/grubGRUB_DISABLE_RECOVERY="true"
Disable vsyscallsxccdf_org.ssgproject.content_rule_grub2_vsyscall_argument medium

Disable vsyscalls

Rule IDxccdf_org.ssgproject.content_rule_grub2_vsyscall_argument
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-grub2_vsyscall_argument:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-001084, CM-7(a), FPT_ASLR_EXT.1, SRG-OS-000480-GPOS-00227, SRG-OS-000134-GPOS-00068

Description
To disable use of virtual syscalls, add the argument vsyscall=none to the default GRUB 2 command line for the Linux operating system. Configure the default Grub2 kernel command line to contain vsyscall=none as follows:
# grub2-editenv - set "$(grub2-editenv - list | grep kernelopts) vsyscall=none"
Rationale
Virtual Syscalls provide an opportunity of attack for a user who has control of the return instruction pointer.

# Remediation is applicable only in certain platforms
if rpm --quiet -q grub2-common && { [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; }; then

grubby --update-kernel=ALL --args=vsyscall=none

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:medium
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-CM-7(a)
    - grub2_vsyscall_argument
    - low_disruption
    - medium_complexity
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Update grub defaults and the bootloader menu
  command: /sbin/grubby --update-kernel=ALL --args="vsyscall=none"
  when:
    - '"grub2-common" in ansible_facts.packages'
    - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-CM-7(a)
    - grub2_vsyscall_argument
    - low_disruption
    - medium_complexity
    - medium_severity
    - reboot_required
    - restrict_strategy

[customizations.kernel]
append = "vsyscall=none"
OVAL test results details

check for vsyscall=none in /etc/default/grub via GRUB_CMDLINE_LINUX  oval:ssg-test_grub2_vsyscall_argument:tst:1  false

Following items have been found on the system:
PathContent
/etc/default/grubGRUB_CMDLINE_LINUX="rd.lvm.lv=fedora_fedora/root rhgb quiet"

check for vsyscall=none in /etc/default/grub via GRUB_CMDLINE_LINUX_DEFAULT  oval:ssg-test_grub2_vsyscall_argument_default:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_grub2_vsyscall_argument_default:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/default/grub^\s*GRUB_CMDLINE_LINUX_DEFAULT="(.*)"$1

Check for GRUB_DISABLE_RECOVERY=true in /etc/default/grub  oval:ssg-test_bootloader_disable_recovery_set_to_true:tst:1  true

Following items have been found on the system:
PathContent
/etc/default/grubGRUB_DISABLE_RECOVERY="true"
Ensure cron Is Logging To Rsyslogxccdf_org.ssgproject.content_rule_rsyslog_cron_logging medium

Ensure cron Is Logging To Rsyslog

Rule IDxccdf_org.ssgproject.content_rule_rsyslog_cron_logging
Result
pass
Multi-check ruleno
OVAL Definition IDoval:ssg-rsyslog_cron_logging:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  1, 14, 15, 16, 3, 5, 6, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS05.04, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, CCI-000366, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, 0988, 1405, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.15.2.1, A.15.2.2, CM-6(a), ID.SC-4, PR.PT-1, FAU_GEN.1.1.c, SRG-OS-000480-GPOS-00227

Description
Cron logging must be implemented to spot intrusions or trace cron job status. If cron is not logging to rsyslog, it can be implemented by adding the following to the RULES section of /etc/rsyslog.conf:
cron.*                                                  /var/log/cron
Rationale
Cron logging can be used to trace the successful or unsuccessful execution of cron jobs. It can also be used to spot intrusions into the use of the cron facility by unauthorized and malicious users.
OVAL test results details

cron is configured in /etc/rsyslog.conf  oval:ssg-test_cron_logging_rsyslog:tst:1  true

Following items have been found on the system:
PathContent
/etc/rsyslog.confcron.* /var/log/cron

cron is configured in /etc/rsyslog.d  oval:ssg-test_cron_logging_rsyslog_dir:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_cron_logging_rsyslog_dir:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/etc/rsyslog.d^.*$^[\s]*cron\.\*[\s]+/var/log/cron$1
Ensure Logs Sent To Remote Hostxccdf_org.ssgproject.content_rule_rsyslog_remote_loghost medium

Ensure Logs Sent To Remote Host

Rule IDxccdf_org.ssgproject.content_rule_rsyslog_remote_loghost
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-rsyslog_remote_loghost:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  BP28(R7), NT28(R43), NT12(R5), 1, 13, 14, 15, 16, 2, 3, 5, 6, APO11.04, APO13.01, BAI03.05, BAI04.04, DSS05.04, DSS05.07, MEA02.01, CCI-000366, CCI-001348, CCI-000136, CCI-001851, 164.308(a)(1)(ii)(D), 164.308(a)(5)(ii)(B), 164.308(a)(5)(ii)(C), 164.308(a)(6)(ii), 164.308(a)(8), 164.310(d)(2)(iii), 164.312(b), 164.314(a)(2)(i)(C), 164.314(a)(2)(iii), 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 7.1, SR 7.2, 0988, 1405, A.12.1.3, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.17.2.1, CIP-003-8 R5.2, CIP-004-6 R3.3, CM-6(a), AU-4(1), AU-9(2), PR.DS-4, PR.PT-1, FAU_GEN.1.1.c, SRG-OS-000479-GPOS-00224, SRG-OS-000480-GPOS-00227, SRG-OS-000342-GPOS-00133, SRG-OS-000032-VMM-000130

Description
To configure rsyslog to send logs to a remote log server, open /etc/rsyslog.conf and read and understand the last section of the file, which describes the multiple directives necessary to activate remote logging. Along with these other directives, the system can be configured to forward its logs to a particular log server by adding or correcting one of the following lines, substituting logcollector appropriately. The choice of protocol depends on the environment of the system; although TCP and RELP provide more reliable message delivery, they may not be supported in all environments.
To use UDP for log message delivery:
*.* @logcollector

To use TCP for log message delivery:
*.* @@logcollector

To use RELP for log message delivery:
*.* :omrelp:logcollector

There must be a resolvable DNS CNAME or Alias record set to "logcollector" for logs to be sent correctly to the centralized logging utility.
Rationale
A log server (loghost) receives syslog messages from one or more systems. This data can be used as an additional log source in the event a system is compromised and its local logs are suspect. Forwarding log messages to a remote loghost also provides system administrators with a centralized place to view the status of multiple hosts within the enterprise.

# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

rsyslog_remote_loghost_address='logcollector'


# Test if the config_file is a symbolic link. If so, use --follow-symlinks with sed.
# Otherwise, regular sed command will do.
sed_command=('sed' '-i')
if test -L "/etc/rsyslog.conf"; then
    sed_command+=('--follow-symlinks')
fi

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^\*\.\*")

# shellcheck disable=SC2059
printf -v formatted_output "%s %s" "$stripped_key" "@@$rsyslog_remote_loghost_address"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^\*\.\*\\>" "/etc/rsyslog.conf"; then
    "${sed_command[@]}" "s/^\*\.\*\\>.*/$formatted_output/gi" "/etc/rsyslog.conf"
else
    # \n is precaution for case where file ends without trailing newline
    
    printf '%s\n' "$formatted_output" >> "/etc/rsyslog.conf"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: XCCDF Value rsyslog_remote_loghost_address # promote to variable
  set_fact:
    rsyslog_remote_loghost_address: !!str logcollector
  tags:
    - always

- name: Set rsyslog remote loghost
  lineinfile:
    dest: /etc/rsyslog.conf
    regexp: ^\*\.\*
    line: '*.* @@{{ rsyslog_remote_loghost_address }}'
    create: true
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-AU-4(1)
    - NIST-800-53-AU-9(2)
    - NIST-800-53-CM-6(a)
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
    - rsyslog_remote_loghost
OVAL test results details

Ensures system configured to export logs to remote host  oval:ssg-test_remote_rsyslog_conf:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_remote_loghost_rsyslog_conf:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/rsyslog.conf^\*\.\*[\s]+(?:@|\:omrelp\:)1

Ensures system configured to export logs to remote host  oval:ssg-test_remote_rsyslog_d:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_remote_loghost_rsyslog_d:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/etc/rsyslog.d^.+\.conf$^\*\.\*[\s]+(?:@|\:omrelp\:)1
Verify firewalld Enabledxccdf_org.ssgproject.content_rule_service_firewalld_enabled medium

Verify firewalld Enabled

Rule IDxccdf_org.ssgproject.content_rule_service_firewalld_enabled
Result
pass
Multi-check ruleno
OVAL Definition IDoval:ssg-service_firewalld_enabled:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  11, 3, 9, BAI10.01, BAI10.02, BAI10.03, BAI10.05, 3.1.3, 3.4.7, CCI-000366, CCI-000382, CCI-002314, 4.3.4.3.2, 4.3.4.3.3, SR 7.6, A.12.1.2, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4, CIP-003-8 R4, CIP-003-8 R5, CIP-004-6 R3, AC-4, CM-7(b), CA-3(5), SC-7(21), CM-6(a), PR.IP-1, FMT_MOF_EXT.1, SRG-OS-000096-GPOS-00050, SRG-OS-000297-GPOS-00115, SRG-OS-000480-GPOS-00227, SRG-OS-000480-GPOS-00231, SRG-OS-000480-GPOS-00232

Description
The firewalld service can be enabled with the following command:
$ sudo systemctl enable firewalld.service
Rationale
Access control methods provide the ability to enhance system security posture by restricting services and known good IP addresses and address ranges. This prevents connections from unknown hosts and protocols.
OVAL test results details

package firewalld is installed  oval:ssg-test_service_firewalld_package_firewalld_installed:tst:1  true

Following items have been found on the system:
NameArchEpochReleaseVersionEvrSignature keyidExtended name
firewalldnoarch(none)1.fc340.9.40:0.9.4-1.fc341161ae6945719a39firewalld-0:0.9.4-1.fc34.noarch

Test that the firewalld service is running  oval:ssg-test_service_running_firewalld:tst:1  true

Following items have been found on the system:
UnitPropertyValue
firewalld.serviceActiveStateactive

systemd test  oval:ssg-test_multi_user_wants_firewalld:tst:1  true

Following items have been found on the system:
UnitDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependency
multi-user.targetbasic.target-.mountsysinit.targetlvm2-lvmpolld.socketsystemd-update-utmp.servicesys-kernel-config.mountcryptsetup.targetsystemd-tmpfiles-setup-dev.servicesystemd-udevd.serviceveritysetup.targetsystemd-ask-password-console.pathsystemd-journal-catalog-update.serviceselinux-autorelabel-mark.servicesystemd-journald.serviceplymouth-start.servicelocal-fs.targetboot.mountsystemd-remount-fs.servicetmp.mountsystemd-repart.serviceswap.targetdev-zram0.swapsystemd-firstboot.servicedracut-shutdown.serviceplymouth-read-write.servicesystemd-udev-trigger.serviceimport-state.servicesystemd-sysctl.servicesystemd-sysusers.serviceproc-sys-fs-binfmt_misc.automountsystemd-journal-flush.servicemultipathd.servicelvm2-monitor.servicedev-hugepages.mountsystemd-update-done.servicesystemd-random-seed.servicedev-mqueue.mountsystemd-hwdb-update.serviceldconfig.servicesystemd-boot-system-token.servicesystemd-machine-id-commit.servicesystemd-tmpfiles-setup.servicesys-kernel-debug.mountiscsi-onboot.servicesys-fs-fuse-connections.mountsys-kernel-tracing.mountkmod-static-nodes.servicesystemd-modules-load.servicesystemd-binfmt.servicepaths.targetrpmdb-rebuild.servicetimers.targetfstrim.timersystemd-tmpfiles-clean.timerlogrotate.timerraid-check.timerdnf-makecache.timermlocate-updatedb.timerunbound-anchor.timerslices.targetsystem.slice-.slicesockets.targetcockpit.socketmultipathd.socketsystemd-udevd-control.socketdbus.socketsystemd-journald-dev-log.socketsssd-kcm.socketsystemd-initctl.socketpcscd.socketsystemd-userdbd.socketiscsid.socketsystemd-coredump.socketdm-event.socketsystemd-udevd-kernel.socketiscsiuio.socketsystemd-journald-audit.socketsystemd-journald.socketsssd.serviceatd.servicegetty.targetgetty@tty1.servicemcelog.serviceabrt-xorg.servicefirewalld.serviceabrt-oops.servicesystemd-resolved.servicesystemd-ask-password-wall.pathrsyslog.serviceabrtd.servicesshd.serviceabrt-journal-core.servicesystemd-update-utmp-runlevel.servicesystemd-oomd.serviceirqbalance.serviceModemManager.serviceplymouth-quit.servicesystemd-logind.servicesmartd.serviceauditd.servicechronyd.serviceremote-fs.targetiscsi.servicenfs-client.targetremote-fs-pre.targetauth-rpcgss-module.servicerpc-statd-notify.servicesystemd-homed.serviceplymouth-quit-wait.servicemdmonitor.serviceNetworkManager.serviceabrt-vmcore.servicesystemd-user-sessions.service

systemd test  oval:ssg-test_multi_user_wants_firewalld_socket:tst:1  false

Following items have been found on the system:
UnitDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependency
multi-user.targetbasic.target-.mountsysinit.targetlvm2-lvmpolld.socketsystemd-update-utmp.servicesys-kernel-config.mountcryptsetup.targetsystemd-tmpfiles-setup-dev.servicesystemd-udevd.serviceveritysetup.targetsystemd-ask-password-console.pathsystemd-journal-catalog-update.serviceselinux-autorelabel-mark.servicesystemd-journald.serviceplymouth-start.servicelocal-fs.targetboot.mountsystemd-remount-fs.servicetmp.mountsystemd-repart.serviceswap.targetdev-zram0.swapsystemd-firstboot.servicedracut-shutdown.serviceplymouth-read-write.servicesystemd-udev-trigger.serviceimport-state.servicesystemd-sysctl.servicesystemd-sysusers.serviceproc-sys-fs-binfmt_misc.automountsystemd-journal-flush.servicemultipathd.servicelvm2-monitor.servicedev-hugepages.mountsystemd-update-done.servicesystemd-random-seed.servicedev-mqueue.mountsystemd-hwdb-update.serviceldconfig.servicesystemd-boot-system-token.servicesystemd-machine-id-commit.servicesystemd-tmpfiles-setup.servicesys-kernel-debug.mountiscsi-onboot.servicesys-fs-fuse-connections.mountsys-kernel-tracing.mountkmod-static-nodes.servicesystemd-modules-load.servicesystemd-binfmt.servicepaths.targetrpmdb-rebuild.servicetimers.targetfstrim.timersystemd-tmpfiles-clean.timerlogrotate.timerraid-check.timerdnf-makecache.timermlocate-updatedb.timerunbound-anchor.timerslices.targetsystem.slice-.slicesockets.targetcockpit.socketmultipathd.socketsystemd-udevd-control.socketdbus.socketsystemd-journald-dev-log.socketsssd-kcm.socketsystemd-initctl.socketpcscd.socketsystemd-userdbd.socketiscsid.socketsystemd-coredump.socketdm-event.socketsystemd-udevd-kernel.socketiscsiuio.socketsystemd-journald-audit.socketsystemd-journald.socketsssd.serviceatd.servicegetty.targetgetty@tty1.servicemcelog.serviceabrt-xorg.servicefirewalld.serviceabrt-oops.servicesystemd-resolved.servicesystemd-ask-password-wall.pathrsyslog.serviceabrtd.servicesshd.serviceabrt-journal-core.servicesystemd-update-utmp-runlevel.servicesystemd-oomd.serviceirqbalance.serviceModemManager.serviceplymouth-quit.servicesystemd-logind.servicesmartd.serviceauditd.servicechronyd.serviceremote-fs.targetiscsi.servicenfs-client.targetremote-fs-pre.targetauth-rpcgss-module.servicerpc-statd-notify.servicesystemd-homed.serviceplymouth-quit-wait.servicemdmonitor.serviceNetworkManager.serviceabrt-vmcore.servicesystemd-user-sessions.service
Set Default firewalld Zone for Incoming Packetsxccdf_org.ssgproject.content_rule_set_firewalld_default_zone medium

Set Default firewalld Zone for Incoming Packets

Rule IDxccdf_org.ssgproject.content_rule_set_firewalld_default_zone
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-set_firewalld_default_zone:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  11, 14, 3, 9, 5.10.1, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS06.06, 3.1.3, 3.4.7, 3.13.6, CCI-000366, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.3.2, 4.3.4.3.3, SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 7.6, 1416, A.12.1.2, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4, A.9.1.2, CA-3(5), CM-7(b), SC-7(23), CM-6(a), PR.IP-1, PR.PT-3, FMT_MOF_EXT.1, SRG-OS-000480-GPOS-00227, SRG-OS-000480-VMM-002000

Description
To set the default zone to drop for the built-in default zone which processes incoming IPv4 and IPv6 packets, modify the following line in /etc/firewalld/firewalld.conf to be:
DefaultZone=drop
Rationale
In firewalld the default zone is applied only after all the applicable rules in the table are examined for a match. Setting the default zone to drop implements proper design for a firewall, i.e. any packets which are not explicitly permitted should not be accepted.
Warnings
warning  To prevent denying any access to the system, automatic remediation of this control is not available. Remediation must be automated as a component of machine provisioning, or followed manually as outlined above.
OVAL test results details

Check /etc/firewalld/firewalld.conf DefaultZone for drop  oval:ssg-test_firewalld_input_drop:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_firewalld_input_drop:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/firewalld/firewalld.conf^DefaultZone=drop$1
Disable ATM Supportxccdf_org.ssgproject.content_rule_kernel_module_atm_disabled medium

Disable ATM Support

Rule IDxccdf_org.ssgproject.content_rule_kernel_module_atm_disabled
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-kernel_module_atm_disabled:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-000381, AC-18, FMT_SMF_EXT.1, SRG-OS-000095-GPOS-00049

Description
The Asynchronous Transfer Mode (ATM) is a protocol operating on network, data link, and physical layers, based on virtual circuits and virtual paths. To configure the system to prevent the atm kernel module from being loaded, add the following line to a file in the directory /etc/modprobe.d:
install atm /bin/true
Rationale
Disabling ATM protects the system against exploitation of any flaws in its implementation.

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

if LC_ALL=C grep -q -m 1 "^install atm" /etc/modprobe.d/atm.conf ; then
	
	sed -i 's#^install atm.*#install atm /bin/true#g' /etc/modprobe.d/atm.conf
else
	echo -e "\n# Disable per security requirements" >> /etc/modprobe.d/atm.conf
	echo "install atm /bin/true" >> /etc/modprobe.d/atm.conf
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Ensure kernel module 'atm' is disabled
  lineinfile:
    create: true
    dest: /etc/modprobe.d/atm.conf
    regexp: atm
    line: install atm /bin/true
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-AC-18
    - disable_strategy
    - kernel_module_atm_disabled
    - low_complexity
    - medium_disruption
    - medium_severity
    - reboot_required

---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,install%20atm%20/bin/true%0A
        mode: 0644
        path: /etc/modprobe.d/75-kernel_module_atm_disabled.conf
        overwrite: true
OVAL test results details

kernel module atm disabled  oval:ssg-test_kernmod_atm_disabled:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_kernmod_atm_disabled:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/etc/modprobe.d^.*\.conf$^\s*install\s+atm\s+(/bin/false|/bin/true)$1

kernel module atm disabled in /etc/modules-load.d  oval:ssg-test_kernmod_atm_etcmodules-load:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_kernmod_atm_etcmodules-load:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/etc/modules-load.d^.*\.conf$^\s*install\s+atm\s+(/bin/false|/bin/true)$1

kernel module atm disabled in /run/modules-load.d  oval:ssg-test_kernmod_atm_runmodules-load:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_kernmod_atm_runmodules-load:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/run/modules-load.d^.*\.conf$^\s*install\s+atm\s+(/bin/false|/bin/true)$1

kernel module atm disabled in /usr/lib/modules-load.d  oval:ssg-test_kernmod_atm_libmodules-load:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_kernmod_atm_libmodules-load:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/usr/lib/modules-load.d^.*\.conf$^\s*install\s+atm\s+(/bin/false|/bin/true)$1

kernel module atm disabled in /run/modprobe.d  oval:ssg-test_kernmod_atm_runmodprobed:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_kernmod_atm_runmodprobed:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/run/modprobe.d^.*\.conf$^\s*install\s+atm\s+(/bin/false|/bin/true)$1

kernel module atm disabled in /usr/lib/modprobe.d  oval:ssg-test_kernmod_atm_libmodprobed:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_kernmod_atm_libmodprobed:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/usr/lib/modprobe.d^.*\.conf$^\s*install\s+atm\s+(/bin/false|/bin/true)$1

kernel module atm disabled in /etc/modprobe.conf  oval:ssg-test_kernmod_atm_modprobeconf:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_kernmod_atm_modprobeconf:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/modprobe.conf^\s*install\s+atm\s+(/bin/false|/bin/true)$1
Disable CAN Supportxccdf_org.ssgproject.content_rule_kernel_module_can_disabled medium

Disable CAN Support

Rule IDxccdf_org.ssgproject.content_rule_kernel_module_can_disabled
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-kernel_module_can_disabled:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-000381, AC-18, FMT_SMF_EXT.1, SRG-OS-000095-GPOS-00049

Description
The Controller Area Network (CAN) is a serial communications protocol which was initially developed for automotive and is now also used in marine, industrial, and medical applications. To configure the system to prevent the can kernel module from being loaded, add the following line to a file in the directory /etc/modprobe.d:
install can /bin/true
Rationale
Disabling CAN protects the system against exploitation of any flaws in its implementation.

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

if LC_ALL=C grep -q -m 1 "^install can" /etc/modprobe.d/can.conf ; then
	
	sed -i 's#^install can.*#install can /bin/true#g' /etc/modprobe.d/can.conf
else
	echo -e "\n# Disable per security requirements" >> /etc/modprobe.d/can.conf
	echo "install can /bin/true" >> /etc/modprobe.d/can.conf
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Ensure kernel module 'can' is disabled
  lineinfile:
    create: true
    dest: /etc/modprobe.d/can.conf
    regexp: can
    line: install can /bin/true
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-AC-18
    - disable_strategy
    - kernel_module_can_disabled
    - low_complexity
    - medium_disruption
    - medium_severity
    - reboot_required

---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,install%20can%20/bin/true%0A
        mode: 0644
        path: /etc/modprobe.d/75-kernel_module_can_disabled.conf
        overwrite: true
OVAL test results details

kernel module can disabled  oval:ssg-test_kernmod_can_disabled:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_kernmod_can_disabled:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/etc/modprobe.d^.*\.conf$^\s*install\s+can\s+(/bin/false|/bin/true)$1

kernel module can disabled in /etc/modules-load.d  oval:ssg-test_kernmod_can_etcmodules-load:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_kernmod_can_etcmodules-load:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/etc/modules-load.d^.*\.conf$^\s*install\s+can\s+(/bin/false|/bin/true)$1

kernel module can disabled in /run/modules-load.d  oval:ssg-test_kernmod_can_runmodules-load:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_kernmod_can_runmodules-load:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/run/modules-load.d^.*\.conf$^\s*install\s+can\s+(/bin/false|/bin/true)$1

kernel module can disabled in /usr/lib/modules-load.d  oval:ssg-test_kernmod_can_libmodules-load:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_kernmod_can_libmodules-load:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/usr/lib/modules-load.d^.*\.conf$^\s*install\s+can\s+(/bin/false|/bin/true)$1

kernel module can disabled in /run/modprobe.d  oval:ssg-test_kernmod_can_runmodprobed:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_kernmod_can_runmodprobed:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/run/modprobe.d^.*\.conf$^\s*install\s+can\s+(/bin/false|/bin/true)$1

kernel module can disabled in /usr/lib/modprobe.d  oval:ssg-test_kernmod_can_libmodprobed:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_kernmod_can_libmodprobed:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/usr/lib/modprobe.d^.*\.conf$^\s*install\s+can\s+(/bin/false|/bin/true)$1

kernel module can disabled in /etc/modprobe.conf  oval:ssg-test_kernmod_can_modprobeconf:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_kernmod_can_modprobeconf:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/modprobe.conf^\s*install\s+can\s+(/bin/false|/bin/true)$1
Disable IEEE 1394 (FireWire) Supportxccdf_org.ssgproject.content_rule_kernel_module_firewire-core_disabled low

Disable IEEE 1394 (FireWire) Support

Rule IDxccdf_org.ssgproject.content_rule_kernel_module_firewire-core_disabled
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-kernel_module_firewire-core_disabled:def:1
Time2024-12-29T17:33:55+01:00
Severitylow
Identifiers and References

References:  CCI-000381, AC-18, FMT_SMF_EXT.1, SRG-OS-000095-GPOS-00049

Description
The IEEE 1394 (FireWire) is a serial bus standard for high-speed real-time communication. To configure the system to prevent the firewire-core kernel module from being loaded, add the following line to a file in the directory /etc/modprobe.d:
install firewire-core /bin/true
Rationale
Disabling FireWire protects the system against exploitation of any flaws in its implementation.

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

if LC_ALL=C grep -q -m 1 "^install firewire-core" /etc/modprobe.d/firewire-core.conf ; then
	
	sed -i 's#^install firewire-core.*#install firewire-core /bin/true#g' /etc/modprobe.d/firewire-core.conf
else
	echo -e "\n# Disable per security requirements" >> /etc/modprobe.d/firewire-core.conf
	echo "install firewire-core /bin/true" >> /etc/modprobe.d/firewire-core.conf
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Ensure kernel module 'firewire-core' is disabled
  lineinfile:
    create: true
    dest: /etc/modprobe.d/firewire-core.conf
    regexp: firewire-core
    line: install firewire-core /bin/true
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-AC-18
    - disable_strategy
    - kernel_module_firewire-core_disabled
    - low_complexity
    - low_severity
    - medium_disruption
    - reboot_required

---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,install%20firewire-core%20/bin/true%0A
        mode: 0644
        path: /etc/modprobe.d/75-kernel_module_firewire-core_disabled.conf
        overwrite: true
OVAL test results details

kernel module firewire-core disabled  oval:ssg-test_kernmod_firewire-core_disabled:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_kernmod_firewire-core_disabled:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/etc/modprobe.d^.*\.conf$^\s*install\s+firewire-core\s+(/bin/false|/bin/true)$1

kernel module firewire-core disabled in /etc/modules-load.d  oval:ssg-test_kernmod_firewire-core_etcmodules-load:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_kernmod_firewire-core_etcmodules-load:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/etc/modules-load.d^.*\.conf$^\s*install\s+firewire-core\s+(/bin/false|/bin/true)$1

kernel module firewire-core disabled in /run/modules-load.d  oval:ssg-test_kernmod_firewire-core_runmodules-load:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_kernmod_firewire-core_runmodules-load:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/run/modules-load.d^.*\.conf$^\s*install\s+firewire-core\s+(/bin/false|/bin/true)$1

kernel module firewire-core disabled in /usr/lib/modules-load.d  oval:ssg-test_kernmod_firewire-core_libmodules-load:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_kernmod_firewire-core_libmodules-load:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/usr/lib/modules-load.d^.*\.conf$^\s*install\s+firewire-core\s+(/bin/false|/bin/true)$1

kernel module firewire-core disabled in /run/modprobe.d  oval:ssg-test_kernmod_firewire-core_runmodprobed:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_kernmod_firewire-core_runmodprobed:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/run/modprobe.d^.*\.conf$^\s*install\s+firewire-core\s+(/bin/false|/bin/true)$1

kernel module firewire-core disabled in /usr/lib/modprobe.d  oval:ssg-test_kernmod_firewire-core_libmodprobed:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_kernmod_firewire-core_libmodprobed:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/usr/lib/modprobe.d^.*\.conf$^\s*install\s+firewire-core\s+(/bin/false|/bin/true)$1

kernel module firewire-core disabled in /etc/modprobe.conf  oval:ssg-test_kernmod_firewire-core_modprobeconf:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_kernmod_firewire-core_modprobeconf:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/modprobe.conf^\s*install\s+firewire-core\s+(/bin/false|/bin/true)$1
Disable TIPC Supportxccdf_org.ssgproject.content_rule_kernel_module_tipc_disabled low

Disable TIPC Support

Rule IDxccdf_org.ssgproject.content_rule_kernel_module_tipc_disabled
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-kernel_module_tipc_disabled:def:1
Time2024-12-29T17:33:55+01:00
Severitylow
Identifiers and References

References:  11, 14, 3, 9, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS06.06, CCI-000381, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.3.2, 4.3.4.3.3, SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 7.6, A.12.1.2, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4, A.9.1.2, CM-7(a), CM-7(b), CM-6(a), PR.IP-1, PR.PT-3, FMT_SMF_EXT.1, SRG-OS-000095-GPOS-00049

Description
The Transparent Inter-Process Communication (TIPC) protocol is designed to provide communications between nodes in a cluster. To configure the system to prevent the tipc kernel module from being loaded, add the following line to a file in the directory /etc/modprobe.d:
install tipc /bin/true
Rationale
Disabling TIPC protects the system against exploitation of any flaws in its implementation.
Warnings
warning  This configuration baseline was created to deploy the base operating system for general purpose workloads. When the operating system is configured for certain purposes, such as a node in High Performance Computing cluster, it is expected that the tipc kernel module will be loaded.

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

if LC_ALL=C grep -q -m 1 "^install tipc" /etc/modprobe.d/tipc.conf ; then
	
	sed -i 's#^install tipc.*#install tipc /bin/true#g' /etc/modprobe.d/tipc.conf
else
	echo -e "\n# Disable per security requirements" >> /etc/modprobe.d/tipc.conf
	echo "install tipc /bin/true" >> /etc/modprobe.d/tipc.conf
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Ensure kernel module 'tipc' is disabled
  lineinfile:
    create: true
    dest: /etc/modprobe.d/tipc.conf
    regexp: tipc
    line: install tipc /bin/true
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-CM-6(a)
    - NIST-800-53-CM-7(a)
    - NIST-800-53-CM-7(b)
    - disable_strategy
    - kernel_module_tipc_disabled
    - low_complexity
    - low_severity
    - medium_disruption
    - reboot_required

---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,install%20tipc%20/bin/true%0A
        mode: 0644
        path: /etc/modprobe.d/75-kernel_module_tipc_disabled.conf
        overwrite: true
OVAL test results details

kernel module tipc disabled  oval:ssg-test_kernmod_tipc_disabled:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_kernmod_tipc_disabled:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/etc/modprobe.d^.*\.conf$^\s*install\s+tipc\s+(/bin/false|/bin/true)$1

kernel module tipc disabled in /etc/modules-load.d  oval:ssg-test_kernmod_tipc_etcmodules-load:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_kernmod_tipc_etcmodules-load:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/etc/modules-load.d^.*\.conf$^\s*install\s+tipc\s+(/bin/false|/bin/true)$1

kernel module tipc disabled in /run/modules-load.d  oval:ssg-test_kernmod_tipc_runmodules-load:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_kernmod_tipc_runmodules-load:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/run/modules-load.d^.*\.conf$^\s*install\s+tipc\s+(/bin/false|/bin/true)$1

kernel module tipc disabled in /usr/lib/modules-load.d  oval:ssg-test_kernmod_tipc_libmodules-load:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_kernmod_tipc_libmodules-load:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/usr/lib/modules-load.d^.*\.conf$^\s*install\s+tipc\s+(/bin/false|/bin/true)$1

kernel module tipc disabled in /run/modprobe.d  oval:ssg-test_kernmod_tipc_runmodprobed:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_kernmod_tipc_runmodprobed:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/run/modprobe.d^.*\.conf$^\s*install\s+tipc\s+(/bin/false|/bin/true)$1

kernel module tipc disabled in /usr/lib/modprobe.d  oval:ssg-test_kernmod_tipc_libmodprobed:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_kernmod_tipc_libmodprobed:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/usr/lib/modprobe.d^.*\.conf$^\s*install\s+tipc\s+(/bin/false|/bin/true)$1

kernel module tipc disabled in /etc/modprobe.conf  oval:ssg-test_kernmod_tipc_modprobeconf:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_kernmod_tipc_modprobeconf:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/modprobe.conf^\s*install\s+tipc\s+(/bin/false|/bin/true)$1
Add nodev Option to /dev/shmxccdf_org.ssgproject.content_rule_mount_option_dev_shm_nodev medium

Add nodev Option to /dev/shm

Rule IDxccdf_org.ssgproject.content_rule_mount_option_dev_shm_nodev
Result
pass
Multi-check ruleno
OVAL Definition IDoval:ssg-mount_option_dev_shm_nodev:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  11, 13, 14, 3, 8, 9, APO13.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS05.06, DSS06.06, CCI-001764, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.3.2, 4.3.4.3.3, SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 7.6, A.11.2.9, A.12.1.2, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4, A.8.2.1, A.8.2.2, A.8.2.3, A.8.3.1, A.8.3.3, A.9.1.2, CIP-003-8 R5.1.1, CIP-003-8 R5.3, CIP-004-6 R2.3, CIP-007-3 R2.1, CIP-007-3 R2.2, CIP-007-3 R2.3, CIP-007-3 R5.1, CIP-007-3 R5.1.1, CIP-007-3 R5.1.2, CM-7(a), CM-7(b), CM-6(a), AC-6, AC-6(1), MP-7, PR.IP-1, PR.PT-2, PR.PT-3, SRG-OS-000368-GPOS-00154

Description
The nodev mount option can be used to prevent creation of device files in /dev/shm. Legitimate character and block devices should not exist within temporary directories like /dev/shm. Add the nodev option to the fourth column of /etc/fstab for the line which controls mounting of /dev/shm.
Rationale
The only legitimate location for device files is the /dev directory located on the root partition. The only exception to this is chroot jails.
OVAL test results details

nodev on /dev/shm optional no  oval:ssg-test_dev_shm_partition_nodev_optional_no:tst:1  true

Following items have been found on the system:
Mount pointDeviceUuidFs typeMount optionsMount optionsMount optionsMount optionsMount optionsTotal spaceSpace usedSpace left
/dev/shmtmpfstmpfsrwseclabelnosuidnodevinode64101772101017721

/dev/shm exists  oval:ssg-test_dev_shm_no_partition_nodev_optional_no:tst:1  true

Following items have been found on the system:
Mount pointDeviceUuidFs typeMount optionsMount optionsMount optionsMount optionsMount optionsTotal spaceSpace usedSpace left
/dev/shmtmpfstmpfsrwseclabelnosuidnodevinode64101772101017721
Add noexec Option to /dev/shmxccdf_org.ssgproject.content_rule_mount_option_dev_shm_noexec medium

Add noexec Option to /dev/shm

Rule IDxccdf_org.ssgproject.content_rule_mount_option_dev_shm_noexec
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-mount_option_dev_shm_noexec:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  11, 13, 14, 3, 8, 9, APO13.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS05.06, DSS06.06, CCI-001764, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.3.2, 4.3.4.3.3, SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 7.6, A.11.2.9, A.12.1.2, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4, A.8.2.1, A.8.2.2, A.8.2.3, A.8.3.1, A.8.3.3, A.9.1.2, CIP-003-8 R5.1.1, CIP-003-8 R5.3, CIP-004-6 R2.3, CIP-007-3 R2.1, CIP-007-3 R2.2, CIP-007-3 R2.3, CIP-007-3 R5.1, CIP-007-3 R5.1.1, CIP-007-3 R5.1.2, CM-7(a), CM-7(b), CM-6(a), AC-6, AC-6(1), MP-7, PR.IP-1, PR.PT-2, PR.PT-3, SRG-OS-000368-GPOS-00154

Description
The noexec mount option can be used to prevent binaries from being executed out of /dev/shm. It can be dangerous to allow the execution of binaries from world-writable temporary storage directories such as /dev/shm. Add the noexec option to the fourth column of /etc/fstab for the line which controls mounting of /dev/shm.
Rationale
Allowing users to execute binaries from world-writable directories such as /dev/shm can expose the system to potential compromise.

# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

function perform_remediation {
    


    mount_point_match_regexp="$(printf "[[:space:]]%s[[:space:]]" /dev/shm)"

    # If the mount point is not in /etc/fstab, get previous mount options from /etc/mtab
    if [ "$(grep -c "$mount_point_match_regexp" /etc/fstab)" -eq 0 ]; then
        # runtime opts without some automatic kernel/userspace-added defaults
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/mtab | head -1 |  awk '{print $4}' \
                    | sed -E "s/(rw|defaults|seclabel|noexec)(,|$)//g;s/,$//")
        [ "$previous_mount_opts" ] && previous_mount_opts+=","
        echo "tmpfs /dev/shm tmpfs defaults,${previous_mount_opts}noexec 0 0" >> /etc/fstab
    # If the mount_opt option is not already in the mount point's /etc/fstab entry, add it
    elif [ "$(grep "$mount_point_match_regexp" /etc/fstab | grep -c "noexec")" -eq 0 ]; then
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/fstab | awk '{print $4}')
        sed -i "s|\(${mount_point_match_regexp}.*${previous_mount_opts}\)|\1,noexec|" /etc/fstab
    fi


    if mkdir -p "/dev/shm"; then
        if mountpoint -q "/dev/shm"; then
            mount -o remount --target "/dev/shm"
        else
            mount --target "/dev/shm"
        fi
    fi
}

perform_remediation

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:high
Strategy:configure
- name: 'Add noexec Option to /dev/shm: Check information associated to mountpoint'
  command: findmnt  '/dev/shm'
  register: device_name
  failed_when: device_name.rc > 1
  changed_when: false
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-AC-6
    - NIST-800-53-AC-6(1)
    - NIST-800-53-CM-6(a)
    - NIST-800-53-CM-7(a)
    - NIST-800-53-CM-7(b)
    - NIST-800-53-MP-7
    - configure_strategy
    - high_disruption
    - low_complexity
    - medium_severity
    - mount_option_dev_shm_noexec
    - no_reboot_needed

- name: 'Add noexec Option to /dev/shm: Create mount_info dictionary variable'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
    - '{{ device_name.stdout_lines[0].split() | list | lower }}'
    - '{{ device_name.stdout_lines[1].split() | list }}'
  when:
    - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
    - device_name.stdout is defined and device_name.stdout_lines is defined
    - (device_name.stdout | length > 0)
  tags:
    - NIST-800-53-AC-6
    - NIST-800-53-AC-6(1)
    - NIST-800-53-CM-6(a)
    - NIST-800-53-CM-7(a)
    - NIST-800-53-CM-7(b)
    - NIST-800-53-MP-7
    - configure_strategy
    - high_disruption
    - low_complexity
    - medium_severity
    - mount_option_dev_shm_noexec
    - no_reboot_needed

- name: 'Add noexec Option to /dev/shm: If /dev/shm not mounted, craft mount_info
    manually'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
    - - target
      - source
      - fstype
      - options
    - - /dev/shm
      - tmpfs
      - tmpfs
      - defaults
  when:
    - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
    - ("" | length == 0)
    - (device_name.stdout | length == 0)
  tags:
    - NIST-800-53-AC-6
    - NIST-800-53-AC-6(1)
    - NIST-800-53-CM-6(a)
    - NIST-800-53-CM-7(a)
    - NIST-800-53-CM-7(b)
    - NIST-800-53-MP-7
    - configure_strategy
    - high_disruption
    - low_complexity
    - medium_severity
    - mount_option_dev_shm_noexec
    - no_reboot_needed

- name: 'Add noexec Option to /dev/shm: Make sure noexec option is part of the to
    /dev/shm options'
  set_fact:
    mount_info: '{{ mount_info | combine( {''options'':''''~mount_info.options~'',noexec''
      }) }}'
  when:
    - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
    - mount_info is defined and "noexec" not in mount_info.options
  tags:
    - NIST-800-53-AC-6
    - NIST-800-53-AC-6(1)
    - NIST-800-53-CM-6(a)
    - NIST-800-53-CM-7(a)
    - NIST-800-53-CM-7(b)
    - NIST-800-53-MP-7
    - configure_strategy
    - high_disruption
    - low_complexity
    - medium_severity
    - mount_option_dev_shm_noexec
    - no_reboot_needed

- name: 'Add noexec Option to /dev/shm: Ensure /dev/shm is mounted with noexec option'
  mount:
    path: /dev/shm
    src: '{{ mount_info.source }}'
    opts: '{{ mount_info.options }}'
    state: mounted
    fstype: '{{ mount_info.fstype }}'
  when:
    - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
    - (device_name.stdout is defined and (device_name.stdout | length > 0)) or (""
      | length == 0)
  tags:
    - NIST-800-53-AC-6
    - NIST-800-53-AC-6(1)
    - NIST-800-53-CM-6(a)
    - NIST-800-53-CM-7(a)
    - NIST-800-53-CM-7(b)
    - NIST-800-53-MP-7
    - configure_strategy
    - high_disruption
    - low_complexity
    - medium_severity
    - mount_option_dev_shm_noexec
    - no_reboot_needed
OVAL test results details

noexec on /dev/shm optional no  oval:ssg-test_dev_shm_partition_noexec_optional_no:tst:1  false

Following items have been found on the system:
Mount pointDeviceUuidFs typeMount optionsMount optionsMount optionsMount optionsMount optionsTotal spaceSpace usedSpace left
/dev/shmtmpfstmpfsrwseclabelnosuidnodevinode64101772101017721

/dev/shm exists  oval:ssg-test_dev_shm_no_partition_noexec_optional_no:tst:1  true

Following items have been found on the system:
Mount pointDeviceUuidFs typeMount optionsMount optionsMount optionsMount optionsMount optionsTotal spaceSpace usedSpace left
/dev/shmtmpfstmpfsrwseclabelnosuidnodevinode64101772101017721
Add nosuid Option to /dev/shmxccdf_org.ssgproject.content_rule_mount_option_dev_shm_nosuid medium

Add nosuid Option to /dev/shm

Rule IDxccdf_org.ssgproject.content_rule_mount_option_dev_shm_nosuid
Result
pass
Multi-check ruleno
OVAL Definition IDoval:ssg-mount_option_dev_shm_nosuid:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  11, 13, 14, 3, 8, 9, APO13.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS05.06, DSS06.06, CCI-001764, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.3.2, 4.3.4.3.3, SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 7.6, A.11.2.9, A.12.1.2, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4, A.8.2.1, A.8.2.2, A.8.2.3, A.8.3.1, A.8.3.3, A.9.1.2, CIP-003-8 R5.1.1, CIP-003-8 R5.3, CIP-004-6 R2.3, CIP-007-3 R2.1, CIP-007-3 R2.2, CIP-007-3 R2.3, CIP-007-3 R5.1, CIP-007-3 R5.1.1, CIP-007-3 R5.1.2, CM-7(a), CM-7(b), CM-6(a), AC-6, AC-6(1), MP-7, PR.IP-1, PR.PT-2, PR.PT-3, SRG-OS-000368-GPOS-00154

Description
The nosuid mount option can be used to prevent execution of setuid programs in /dev/shm. The SUID and SGID permissions should not be required in these world-writable directories. Add the nosuid option to the fourth column of /etc/fstab for the line which controls mounting of /dev/shm.
Rationale
The presence of SUID and SGID executables should be tightly controlled. Users should not be able to execute SUID or SGID binaries from temporary storage partitions.
OVAL test results details

nosuid on /dev/shm optional no  oval:ssg-test_dev_shm_partition_nosuid_optional_no:tst:1  true

Following items have been found on the system:
Mount pointDeviceUuidFs typeMount optionsMount optionsMount optionsMount optionsMount optionsTotal spaceSpace usedSpace left
/dev/shmtmpfstmpfsrwseclabelnosuidnodevinode64101772101017721

/dev/shm exists  oval:ssg-test_dev_shm_no_partition_nosuid_optional_no:tst:1  true

Following items have been found on the system:
Mount pointDeviceUuidFs typeMount optionsMount optionsMount optionsMount optionsMount optionsTotal spaceSpace usedSpace left
/dev/shmtmpfstmpfsrwseclabelnosuidnodevinode64101772101017721
Disable acquiring, saving, and processing core dumpsxccdf_org.ssgproject.content_rule_service_systemd-coredump_disabled medium

Disable acquiring, saving, and processing core dumps

Rule IDxccdf_org.ssgproject.content_rule_service_systemd-coredump_disabled
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-service_systemd-coredump_disabled:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-000366, SC-7(10), FMT_SMF_EXT.1, SRG-OS-000480-GPOS-00227

Description
The systemd-coredump.socket unit is a socket activation of the systemd-coredump@.service which processes core dumps. By masking the unit, core dump processing is disabled.
Rationale
A core dump includes a memory image taken at the time the operating system terminates an application. The memory image could contain sensitive data and is generally useful only for developers trying to debug problems.

Complexity:low
Disruption:low
Strategy:disable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

SYSTEMCTL_EXEC='/usr/bin/systemctl'
"$SYSTEMCTL_EXEC" stop 'systemd-coredump.service'
"$SYSTEMCTL_EXEC" disable 'systemd-coredump.service'
"$SYSTEMCTL_EXEC" mask 'systemd-coredump.service'
# Disable socket activation if we have a unit file for it
if "$SYSTEMCTL_EXEC" list-unit-files | grep -q '^systemd-coredump.socket'; then
    "$SYSTEMCTL_EXEC" stop 'systemd-coredump.socket'
    "$SYSTEMCTL_EXEC" mask 'systemd-coredump.socket'
fi
# The service may not be running because it has been started and failed,
# so let's reset the state so OVAL checks pass.
# Service should be 'inactive', not 'failed' after reboot though.
"$SYSTEMCTL_EXEC" reset-failed 'systemd-coredump.service' || true

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:disable
- name: Disable service systemd-coredump
  block:

    - name: Disable service systemd-coredump
      systemd:
        name: systemd-coredump.service
        enabled: 'no'
        state: stopped
        masked: 'yes'
      ignore_errors: 'yes'
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-SC-7(10)
    - disable_strategy
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - service_systemd-coredump_disabled

- name: Unit Socket Exists - systemd-coredump.socket
  command: systemctl list-unit-files systemd-coredump.socket
  args:
    warn: false
  register: socket_file_exists
  changed_when: false
  ignore_errors: true
  check_mode: false
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-SC-7(10)
    - disable_strategy
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - service_systemd-coredump_disabled

- name: Disable socket systemd-coredump
  systemd:
    name: systemd-coredump.socket
    enabled: 'no'
    state: stopped
    masked: 'yes'
  when:
    - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
    - '"systemd-coredump.socket" in socket_file_exists.stdout_lines[1]'
  tags:
    - NIST-800-53-SC-7(10)
    - disable_strategy
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - service_systemd-coredump_disabled

Complexity:low
Disruption:low
Strategy:enable
include disable_systemd-coredump

class disable_systemd-coredump {
  service {'systemd-coredump':
    enable => false,
    ensure => 'stopped',
  }
}

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    systemd:
      units:
      - name: systemd-coredump.service
        enabled: false
        mask: true
      - name: systemd-coredump.socket
        enabled: false
        mask: true


[customizations.services]
disabled = ["systemd-coredump"]
OVAL test results details

package systemd is removed  oval:ssg-test_service_systemd-coredump_package_systemd_removed:tst:1  false

Following items have been found on the system:
NameArchEpochReleaseVersionEvrSignature keyidExtended name
systemdx86_64(none)1.fc34248.100:248.10-1.fc341161ae6945719a39systemd-0:248.10-1.fc34.x86_64

Test that the systemd-coredump service is not running  oval:ssg-test_service_not_running_systemd-coredump:tst:1  false

Following items have been found on the system:
UnitPropertyValue
systemd-coredump.socketActiveStateactive

Test that the property LoadState from the service systemd-coredump is masked  oval:ssg-test_service_loadstate_is_masked_systemd-coredump:tst:1  false

Following items have been found on the system:
UnitPropertyValue
systemd-coredump.socketLoadStateloaded
Disable core dump backtracesxccdf_org.ssgproject.content_rule_coredump_disable_backtraces medium

Disable core dump backtraces

Rule IDxccdf_org.ssgproject.content_rule_coredump_disable_backtraces
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-coredump_disable_backtraces:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-000366, CM-6, FMT_SMF_EXT.1, SRG-OS-000480-GPOS-00227

Description
The ProcessSizeMax option in [Coredump] section of /etc/systemd/coredump.conf specifies the maximum size in bytes of a core which will be processed. Core dumps exceeding this size may be stored, but the backtrace will not be generated.
Rationale
A core dump includes a memory image taken at the time the operating system terminates an application. The memory image could contain sensitive data and is generally useful only for developers or system operators trying to debug problems. Enabling core dumps on production systems is not recommended, however there may be overriding operational requirements to enable advanced debuging. Permitting temporary enablement of core dumps during such situations should be reviewed through local needs and policy.
Warnings
warning  If the /etc/systemd/coredump.conf file does not already contain the [Coredump] section, the value will not be configured correctly.

Complexity:low
Disruption:low
Strategy:restrict
if [ -e "/etc/systemd/coredump.conf" ] ; then
    
    LC_ALL=C sed -i "/^\s*ProcessSizeMax\s*=\s*/Id" "/etc/systemd/coredump.conf"
else
    touch "/etc/systemd/coredump.conf"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/systemd/coredump.conf"

cp "/etc/systemd/coredump.conf" "/etc/systemd/coredump.conf.bak"
# Insert at the end of the file
printf '%s\n' "ProcessSizeMax=0" >> "/etc/systemd/coredump.conf"
# Clean up after ourselves.
rm "/etc/systemd/coredump.conf.bak"

Complexity:low
Disruption:low
Strategy:restrict
- name: Disable core dump backtraces
  block:

    - name: Check for duplicate values
      lineinfile:
        path: /etc/systemd/coredump.conf
        create: false
        regexp: ^\s*ProcessSizeMax\s*=\s*
        state: absent
      check_mode: true
      changed_when: false
      register: dupes

    - name: Deduplicate values from /etc/systemd/coredump.conf
      lineinfile:
        path: /etc/systemd/coredump.conf
        create: false
        regexp: ^\s*ProcessSizeMax\s*=\s*
        state: absent
      when: dupes.found is defined and dupes.found > 1

    - name: Insert correct line to /etc/systemd/coredump.conf
      lineinfile:
        path: /etc/systemd/coredump.conf
        create: false
        regexp: ^\s*ProcessSizeMax\s*=\s*
        line: ProcessSizeMax=0
        state: present
  tags:
    - NIST-800-53-CM-6
    - coredump_disable_backtraces
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,%23%20%20This%20file%20is%20part%20of%20systemd.%0A%23%0A%23%20%20systemd%20is%20free%20software%3B%20you%20can%20redistribute%20it%20and/or%20modify%20it%0A%23%20%20under%20the%20terms%20of%20the%20GNU%20Lesser%20General%20Public%20License%20as%20published%20by%0A%23%20%20the%20Free%20Software%20Foundation%3B%20either%20version%202.1%20of%20the%20License%2C%20or%0A%23%20%20%28at%20your%20option%29%20any%20later%20version.%0A%23%0A%23%20Entries%20in%20this%20file%20show%20the%20compile%20time%20defaults.%0A%23%20You%20can%20change%20settings%20by%20editing%20this%20file.%0A%23%20Defaults%20can%20be%20restored%20by%20simply%20deleting%20this%20file.%0A%23%0A%23%20See%20coredump.conf%285%29%20for%20details.%0A%0A%5BCoredump%5D%0A%23Storage%3Dexternal%0A%23Compress%3Dyes%0A%23ProcessSizeMax%3D2G%0A%23ExternalSizeMax%3D2G%0A%23JournalSizeMax%3D767M%0A%23MaxUse%3D%0A%23KeepFree%3D%0AStorage%3Dnone%0AProcessSizeMax%3D0%0A
        mode: 0644
        path: /etc/systemd/coredump.conf
        overwrite: true
OVAL test results details

tests the value of ProcessSizeMax setting in the /etc/systemd/coredump.conf file  oval:ssg-test_coredump_disable_backtraces:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_coredump_disable_backtraces:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/systemd/coredump.conf^\s*\[Coredump\].*(?:\n\s*[^[\s].*)*\n^[ \t]*(?i)ProcessSizeMax(?-i)[ \t]*=[ \t]*(.+?)[ \t]*(?:$|#)1
Disable storing core dumpxccdf_org.ssgproject.content_rule_coredump_disable_storage medium

Disable storing core dump

Rule IDxccdf_org.ssgproject.content_rule_coredump_disable_storage
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-coredump_disable_storage:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-000366, CM-6, FMT_SMF_EXT.1, SRG-OS-000480-GPOS-00227

Description
The Storage option in [Coredump] section of /etc/systemd/coredump.conf can be set to none to disable storing core dumps permanently.
Rationale
A core dump includes a memory image taken at the time the operating system terminates an application. The memory image could contain sensitive data and is generally useful only for developers or system operators trying to debug problems. Enabling core dumps on production systems is not recommended, however there may be overriding operational requirements to enable advanced debuging. Permitting temporary enablement of core dumps during such situations should be reviewed through local needs and policy.
Warnings
warning  If the /etc/systemd/coredump.conf file does not already contain the [Coredump] section, the value will not be configured correctly.

Complexity:low
Disruption:low
Strategy:restrict
if [ -e "/etc/systemd/coredump.conf" ] ; then
    
    LC_ALL=C sed -i "/^\s*Storage\s*=\s*/Id" "/etc/systemd/coredump.conf"
else
    touch "/etc/systemd/coredump.conf"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/systemd/coredump.conf"

cp "/etc/systemd/coredump.conf" "/etc/systemd/coredump.conf.bak"
# Insert at the end of the file
printf '%s\n' "Storage=none" >> "/etc/systemd/coredump.conf"
# Clean up after ourselves.
rm "/etc/systemd/coredump.conf.bak"

Complexity:low
Disruption:low
Strategy:restrict
- name: Disable storing core dump
  block:

    - name: Check for duplicate values
      lineinfile:
        path: /etc/systemd/coredump.conf
        create: false
        regexp: ^\s*Storage\s*=\s*
        state: absent
      check_mode: true
      changed_when: false
      register: dupes

    - name: Deduplicate values from /etc/systemd/coredump.conf
      lineinfile:
        path: /etc/systemd/coredump.conf
        create: false
        regexp: ^\s*Storage\s*=\s*
        state: absent
      when: dupes.found is defined and dupes.found > 1

    - name: Insert correct line to /etc/systemd/coredump.conf
      lineinfile:
        path: /etc/systemd/coredump.conf
        create: false
        regexp: ^\s*Storage\s*=\s*
        line: Storage=none
        state: present
  tags:
    - NIST-800-53-CM-6
    - coredump_disable_storage
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy

---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,%23%20%20This%20file%20is%20part%20of%20systemd.%0A%23%0A%23%20%20systemd%20is%20free%20software%3B%20you%20can%20redistribute%20it%20and/or%20modify%20it%0A%23%20%20under%20the%20terms%20of%20the%20GNU%20Lesser%20General%20Public%20License%20as%20published%20by%0A%23%20%20the%20Free%20Software%20Foundation%3B%20either%20version%202.1%20of%20the%20License%2C%20or%0A%23%20%20%28at%20your%20option%29%20any%20later%20version.%0A%23%0A%23%20Entries%20in%20this%20file%20show%20the%20compile%20time%20defaults.%0A%23%20You%20can%20change%20settings%20by%20editing%20this%20file.%0A%23%20Defaults%20can%20be%20restored%20by%20simply%20deleting%20this%20file.%0A%23%0A%23%20See%20coredump.conf%285%29%20for%20details.%0A%0A%5BCoredump%5D%0A%23Storage%3Dexternal%0A%23Compress%3Dyes%0A%23ProcessSizeMax%3D2G%0A%23ExternalSizeMax%3D2G%0A%23JournalSizeMax%3D767M%0A%23MaxUse%3D%0A%23KeepFree%3D%0AStorage%3Dnone%0AProcessSizeMax%3D0%0A
        mode: 0644
        path: /etc/systemd/coredump.conf
        overwrite: true
OVAL test results details

tests the value of Storage setting in the /etc/systemd/coredump.conf file  oval:ssg-test_coredump_disable_storage:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_coredump_disable_storage:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/systemd/coredump.conf^\s*\[Coredump\].*(?:\n\s*[^[\s].*)*\n^[ \t]*(?i)Storage(?-i)[ \t]*=[ \t]*(.+?)[ \t]*(?:$|#)1
Restrict Exposed Kernel Pointer Addresses Accessxccdf_org.ssgproject.content_rule_sysctl_kernel_kptr_restrict medium

Restrict Exposed Kernel Pointer Addresses Access

Rule IDxccdf_org.ssgproject.content_rule_sysctl_kernel_kptr_restrict
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-sysctl_kernel_kptr_restrict:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  BP28(R23), CCI-002824, CCI-000366, CIP-002-5 R1.1, CIP-002-5 R1.2, CIP-003-8 R5.1.1, CIP-003-8 R5.3, CIP-004-6 4.1, CIP-004-6 4.2, CIP-004-6 R2.2.3, CIP-004-6 R2.2.4, CIP-004-6 R2.3, CIP-004-6 R4, CIP-005-6 R1, CIP-005-6 R1.1, CIP-005-6 R1.2, CIP-007-3 R3, CIP-007-3 R3.1, CIP-007-3 R5.1, CIP-007-3 R5.1.2, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3, CIP-007-3 R8.4, CIP-009-6 R.1.1, CIP-009-6 R4, SC-30, SC-30(2), SC-30(5), CM-6(a), SRG-OS-000132-GPOS-00067, SRG-OS-000433-GPOS-00192, SRG-OS-000480-GPOS-00227

Description
To set the runtime status of the kernel.kptr_restrict kernel parameter, run the following command:
$ sudo sysctl -w kernel.kptr_restrict=1
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
kernel.kptr_restrict = 1
Rationale
Exposing kernel pointers (through procfs or seq_printf()) exposes kernel writeable structures that can contain functions pointers. If a write vulnereability occurs in the kernel allowing a write access to any of this structure, the kernel can be compromise. This option disallow any program withtout the CAP_SYSLOG capability from getting the kernel pointers addresses, replacing them with 0.

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

# Comment out any occurrences of kernel.kptr_restrict from /etc/sysctl.d/*.conf files
for f in /etc/sysctl.d/*.conf ; do
  matching_list=$(grep -P '^(?!#).*[\s]+kernel.kptr_restrict.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      # comment out "kernel.kptr_restrict" matches to preserve user data
      sed -i "s/^${entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done
sysctl_kernel_kptr_restrict_value='1'


#
# Set runtime for kernel.kptr_restrict
#
/sbin/sysctl -q -n -w kernel.kptr_restrict="$sysctl_kernel_kptr_restrict_value"

#
# If kernel.kptr_restrict present in /etc/sysctl.conf, change value to appropriate value
#	else, add "kernel.kptr_restrict = value" to /etc/sysctl.conf
#
# Test if the config_file is a symbolic link. If so, use --follow-symlinks with sed.
# Otherwise, regular sed command will do.
sed_command=('sed' '-i')
if test -L "/etc/sysctl.conf"; then
    sed_command+=('--follow-symlinks')
fi

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^kernel.kptr_restrict")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "$sysctl_kernel_kptr_restrict_value"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^kernel.kptr_restrict\\>" "/etc/sysctl.conf"; then
    "${sed_command[@]}" "s/^kernel.kptr_restrict\\>.*/$formatted_output/gi" "/etc/sysctl.conf"
else
    # \n is precaution for case where file ends without trailing newline
    
    printf '%s\n' "$formatted_output" >> "/etc/sysctl.conf"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: List /etc/sysctl.d/*.conf files
  find:
    paths: /etc/sysctl.d/
    contains: ^[\s]*kernel.kptr_restrict.*$
    patterns: '*.conf'
  register: find_sysctl_d
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-CM-6(a)
    - NIST-800-53-SC-30
    - NIST-800-53-SC-30(2)
    - NIST-800-53-SC-30(5)
    - disable_strategy
    - low_complexity
    - medium_disruption
    - medium_severity
    - reboot_required
    - sysctl_kernel_kptr_restrict

- name: Comment out any occurrences of kernel.kptr_restrict from /etc/sysctl.d/*.conf
    files
  replace:
    path: '{{ item }}'
    regexp: ^[\s]*kernel.kptr_restrict
    replace: '#kernel.kptr_restrict'
  loop: '{{ find_sysctl_d.files }}'
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-CM-6(a)
    - NIST-800-53-SC-30
    - NIST-800-53-SC-30(2)
    - NIST-800-53-SC-30(5)
    - disable_strategy
    - low_complexity
    - medium_disruption
    - medium_severity
    - reboot_required
    - sysctl_kernel_kptr_restrict
- name: XCCDF Value sysctl_kernel_kptr_restrict_value # promote to variable
  set_fact:
    sysctl_kernel_kptr_restrict_value: !!str 1
  tags:
    - always

- name: Ensure sysctl kernel.kptr_restrict is set
  sysctl:
    name: kernel.kptr_restrict
    value: '{{ sysctl_kernel_kptr_restrict_value }}'
    state: present
    reload: true
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-CM-6(a)
    - NIST-800-53-SC-30
    - NIST-800-53-SC-30(2)
    - NIST-800-53-SC-30(5)
    - disable_strategy
    - low_complexity
    - medium_disruption
    - medium_severity
    - reboot_required
    - sysctl_kernel_kptr_restrict

---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,kernel.kptr_restrict%3D1%0A
        mode: 0644
        path: /etc/sysctl.d/75-sysctl_kernel_kptr_restrict.conf
        overwrite: true
OVAL test results details

kernel.kptr_restrict static configuration  oval:ssg-test_static_sysctl_kernel_kptr_restrict:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_sysctl_kernel_kptr_restrict:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/sysctl.conf(?:^|.*\n)[^#]*kernel.kptr_restrict[\s]*=[\s]*(\d+)[\s]*\n1

kernel.kptr_restrict static configuration in /etc/sysctl.d/*.conf  oval:ssg-test_static_etc_sysctld_kernel_kptr_restrict:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_etc_sysctld_kernel_kptr_restrict:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/etc/sysctl.d^.*\.conf$(?:^|.*\n)[^#]*kernel.kptr_restrict[\s]*=[\s]*(\d+)[\s]*\n1

kernel.kptr_restrict static configuration in /etc/sysctl.d/*.conf  oval:ssg-test_static_run_sysctld_kernel_kptr_restrict:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_run_sysctld_kernel_kptr_restrict:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/run/sysctl.d^.*\.conf$(?:^|.*\n)[^#]*kernel.kptr_restrict[\s]*=[\s]*(\d+)[\s]*\n1

kernel.kptr_restrict static configuration in /etc/sysctl.d/*.conf  oval:ssg-test_static_usr_lib_sysctld_kernel_kptr_restrict:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_usr_lib_sysctld_kernel_kptr_restrict:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/usr/lib/sysctl.d^.*\.conf$(?:^|.*\n)[^#]*kernel.kptr_restrict[\s]*=[\s]*(\d+)[\s]*\n1

kernel runtime parameter kernel.kptr_restrict set to the appropriate value  oval:ssg-test_sysctl_runtime_kernel_kptr_restrict:tst:1  false

Following items have been found on the system:
NameValue
kernel.kptr_restrict0
Enable page allocator poisoningxccdf_org.ssgproject.content_rule_grub2_page_poison_argument medium

Enable page allocator poisoning

Rule IDxccdf_org.ssgproject.content_rule_grub2_page_poison_argument
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-grub2_page_poison_argument:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-001084, CM-6(a), SRG-OS-000480-GPOS-00227, SRG-OS-000134-GPOS-00068

Description
To enable poisoning of free pages, add the argument page_poison=1 to the default GRUB 2 command line for the Linux operating system. Configure the default Grub2 kernel command line to contain page_poison=1 as follows:
# grub2-editenv - set "$(grub2-editenv - list | grep kernelopts) page_poison=1"
Rationale
Poisoning writes an arbitrary value to freed pages, so any modification or reference to that page after being freed or before being initialized will be detected and prevented. This prevents many types of use-after-free vulnerabilities at little performance cost. Also prevents leak of data and detection of corrupted memory.

# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && { rpm --quiet -q grub2-common; }; then

grubby --update-kernel=ALL --args=page_poison=1

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:medium
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-CM-6(a)
    - grub2_page_poison_argument
    - low_disruption
    - medium_complexity
    - medium_severity
    - reboot_required
    - restrict_strategy

- name: Update grub defaults and the bootloader menu
  command: /sbin/grubby --update-kernel=ALL --args="page_poison=1"
  when:
    - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
    - '"grub2-common" in ansible_facts.packages'
  tags:
    - NIST-800-53-CM-6(a)
    - grub2_page_poison_argument
    - low_disruption
    - medium_complexity
    - medium_severity
    - reboot_required
    - restrict_strategy

[customizations.kernel]
append = "page_poison=1"
OVAL test results details

check for page_poison=1 in /etc/default/grub via GRUB_CMDLINE_LINUX  oval:ssg-test_grub2_page_poison_argument:tst:1  false

Following items have been found on the system:
PathContent
/etc/default/grubGRUB_CMDLINE_LINUX="rd.lvm.lv=fedora_fedora/root rhgb quiet"

check for page_poison=1 in /etc/default/grub via GRUB_CMDLINE_LINUX_DEFAULT  oval:ssg-test_grub2_page_poison_argument_default:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_grub2_page_poison_argument_default:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/default/grub^\s*GRUB_CMDLINE_LINUX_DEFAULT="(.*)"$1

Check for GRUB_DISABLE_RECOVERY=true in /etc/default/grub  oval:ssg-test_bootloader_disable_recovery_set_to_true:tst:1  true

Following items have been found on the system:
PathContent
/etc/default/grubGRUB_DISABLE_RECOVERY="true"
Enable SLUB/SLAB allocator poisoningxccdf_org.ssgproject.content_rule_grub2_slub_debug_argument medium

Enable SLUB/SLAB allocator poisoning

Rule IDxccdf_org.ssgproject.content_rule_grub2_slub_debug_argument
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-grub2_slub_debug_argument:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-001084, CM-6(a), SRG-OS-000433-GPOS-00192, SRG-OS-000134-GPOS-00068

Description
To enable poisoning of SLUB/SLAB objects, add the argument slub_debug=P to the default GRUB 2 command line for the Linux operating system. Configure the default Grub2 kernel command line to contain slub_debug=P as follows:
# grub2-editenv - set "$(grub2-editenv - list | grep kernelopts) slub_debug=P"
Rationale
Poisoning writes an arbitrary value to freed objects, so any modification or reference to that object after being freed or before being initialized will be detected and prevented. This prevents many types of use-after-free vulnerabilities at little performance cost. Also prevents leak of data and detection of corrupted memory.

# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && { rpm --quiet -q grub2-common; }; then

var_slub_debug_options='P'




	grubby --update-kernel=ALL --args=slub_debug=$var_slub_debug_options

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:medium
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
    - NIST-800-53-CM-6(a)
    - grub2_slub_debug_argument
    - low_disruption
    - medium_complexity
    - medium_severity
    - reboot_required
    - restrict_strategy
- name: XCCDF Value var_slub_debug_options # promote to variable
  set_fact:
    var_slub_debug_options: !!str P
  tags:
    - always

- name: Update grub defaults and the bootloader menu
  command: /sbin/grubby --update-kernel=ALL --args="slub_debug={{ var_slub_debug_options
    }}"
  when:
    - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
    - '"grub2-common" in ansible_facts.packages'
  tags:
    - NIST-800-53-CM-6(a)
    - grub2_slub_debug_argument
    - low_disruption
    - medium_complexity
    - medium_severity
    - reboot_required
    - restrict_strategy

[customizations.kernel]
append = "slub_debug=P"
OVAL test results details

check for slub_debug in /etc/default/grub via GRUB_CMDLINE_LINUX  oval:ssg-test_grub2_slub_debug_argument:tst:1  false

Following items have been found on the system:
PathContent
/etc/default/grubGRUB_CMDLINE_LINUX="rd.lvm.lv=fedora_fedora/root rhgb quiet"

check for slub_debug in /etc/default/grub via GRUB_CMDLINE_LINUX_DEFAULT  oval:ssg-test_grub2_slub_debug_argument_default:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_grub2_slub_debug_argument_default:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/default/grub^\s*GRUB_CMDLINE_LINUX_DEFAULT="(.*)"$1

Check for GRUB_DISABLE_RECOVERY=true in /etc/default/grub  oval:ssg-test_bootloader_disable_recovery_set_to_true:tst:1  true

Following items have been found on the system:
PathContent
/etc/default/grubGRUB_DISABLE_RECOVERY="true"
Disable storing core dumpsxccdf_org.ssgproject.content_rule_sysctl_kernel_core_pattern medium

Disable storing core dumps

Rule IDxccdf_org.ssgproject.content_rule_sysctl_kernel_core_pattern
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-sysctl_kernel_core_pattern:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-000366, SC-7(10), FMT_SMF_EXT.1, SRG-OS-000480-GPOS-00227

Description
To set the runtime status of the kernel.core_pattern kernel parameter, run the following command:
$ sudo sysctl -w kernel.core_pattern=|/bin/false
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
kernel.core_pattern = |/bin/false
Rationale
A core dump includes a memory image taken at the time the operating system terminates an application. The memory image could contain sensitive data and is generally useful only for developers trying to debug problems.

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

# Comment out any occurrences of kernel.core_pattern from /etc/sysctl.d/*.conf files
for f in /etc/sysctl.d/*.conf ; do
  matching_list=$(grep -P '^(?!#).*[\s]+kernel.core_pattern.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      # comment out "kernel.core_pattern" matches to preserve user data
      sed -i "s/^${entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

#
# Set runtime for kernel.core_pattern
#
/sbin/sysctl -q -n -w kernel.core_pattern="|/bin/false"

#
# If kernel.core_pattern present in /etc/sysctl.conf, change value to "|/bin/false"
#	else, add "kernel.core_pattern = |/bin/false" to /etc/sysctl.conf
#
# Test if the config_file is a symbolic link. If so, use --follow-symlinks with sed.
# Otherwise, regular sed command will do.
sed_command=('sed' '-i')
if test -L "/etc/sysctl.conf"; then
    sed_command+=('--follow-symlinks')
fi

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^kernel.core_pattern")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "|/bin/false"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^kernel.core_pattern\\>" "/etc/sysctl.conf"; then
    "${sed_command[@]}" "s/^kernel.core_pattern\\>.*/$formatted_output/gi" "/etc/sysctl.conf"
else
    # \n is precaution for case where file ends without trailing newline
    
    printf '%s\n' "$formatted_output" >> "/etc/sysctl.conf"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: List /etc/sysctl.d/*.conf files
  find:
    paths: /etc/sysctl.d/
    contains: ^[\s]*kernel.core_pattern.*$
    patterns: '*.conf'
  register: find_sysctl_d
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-SC-7(10)
    - disable_strategy
    - low_complexity
    - medium_disruption
    - medium_severity
    - reboot_required
    - sysctl_kernel_core_pattern

- name: Comment out any occurrences of kernel.core_pattern from /etc/sysctl.d/*.conf
    files
  replace:
    path: '{{ item }}'
    regexp: ^[\s]*kernel.core_pattern
    replace: '#kernel.core_pattern'
  loop: '{{ find_sysctl_d.files }}'
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-SC-7(10)
    - disable_strategy
    - low_complexity
    - medium_disruption
    - medium_severity
    - reboot_required
    - sysctl_kernel_core_pattern

- name: Ensure sysctl kernel.core_pattern is set to |/bin/false
  sysctl:
    name: kernel.core_pattern
    value: '|/bin/false'
    state: present
    reload: true
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-SC-7(10)
    - disable_strategy
    - low_complexity
    - medium_disruption
    - medium_severity
    - reboot_required
    - sysctl_kernel_core_pattern

---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,kernel.core_pattern%20%3D%20%7C/bin/false%0A
        mode: 0644
        path: /etc/sysctl.d/75-sysctl_kernel_core_pattern.conf
        overwrite: true
OVAL test results details

kernel.core_pattern static configuration  oval:ssg-test_static_sysctl_kernel_core_pattern:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_sysctl_kernel_core_pattern:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/sysctl.conf^[\s]*kernel.core_pattern[\s]*=[\s]*|/bin/false[\s]*$1

kernel.core_pattern static configuration in /etc/sysctl.d/*.conf  oval:ssg-test_static_etc_sysctld_kernel_core_pattern:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_etc_sysctld_kernel_core_pattern:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/etc/sysctl.d^.*\.conf$^[\s]*kernel.core_pattern[\s]*=[\s]*|/bin/false[\s]*$1

kernel.core_pattern static configuration in /etc/sysctl.d/*.conf  oval:ssg-test_static_run_sysctld_kernel_core_pattern:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_run_sysctld_kernel_core_pattern:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/run/sysctl.d^.*\.conf$^[\s]*kernel.core_pattern[\s]*=[\s]*|/bin/false[\s]*$1

kernel.core_pattern static configuration in /etc/sysctl.d/*.conf  oval:ssg-test_static_usr_lib_sysctld_kernel_core_pattern:tst:1  true

Following items have been found on the system:
PathContent
/usr/lib/sysctl.d/50-coredump.confkernel.core_pattern=

kernel runtime parameter kernel.core_pattern set to |/bin/false  oval:ssg-test_sysctl_runtime_kernel_core_pattern:tst:1  false

Following items have been found on the system:
NameValue
kernel.core_pattern|/usr/lib/systemd/systemd-coredump %P %u %g %s %t %c %h
Restrict Access to Kernel Message Bufferxccdf_org.ssgproject.content_rule_sysctl_kernel_dmesg_restrict low

Restrict Access to Kernel Message Buffer

Rule IDxccdf_org.ssgproject.content_rule_sysctl_kernel_dmesg_restrict
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-sysctl_kernel_dmesg_restrict:def:1
Time2024-12-29T17:33:55+01:00
Severitylow
Identifiers and References

References:  BP28(R23), 3.1.5, CCI-001314, 164.308(a)(1)(ii)(D), 164.308(a)(3), 164.308(a)(4), 164.310(b), 164.310(c), 164.312(a), 164.312(e), SI-11(a), SI-11(b), SRG-OS-000132-GPOS-00067, SRG-OS-000138-GPOS-00069

Description
To set the runtime status of the kernel.dmesg_restrict kernel parameter, run the following command:
$ sudo sysctl -w kernel.dmesg_restrict=1
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
kernel.dmesg_restrict = 1
Rationale
Unprivileged access to the kernel syslog can expose sensitive kernel address information.

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

# Comment out any occurrences of kernel.dmesg_restrict from /etc/sysctl.d/*.conf files
for f in /etc/sysctl.d/*.conf ; do
  matching_list=$(grep -P '^(?!#).*[\s]+kernel.dmesg_restrict.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      # comment out "kernel.dmesg_restrict" matches to preserve user data
      sed -i "s/^${entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

#
# Set runtime for kernel.dmesg_restrict
#
/sbin/sysctl -q -n -w kernel.dmesg_restrict="1"

#
# If kernel.dmesg_restrict present in /etc/sysctl.conf, change value to "1"
#	else, add "kernel.dmesg_restrict = 1" to /etc/sysctl.conf
#
# Test if the config_file is a symbolic link. If so, use --follow-symlinks with sed.
# Otherwise, regular sed command will do.
sed_command=('sed' '-i')
if test -L "/etc/sysctl.conf"; then
    sed_command+=('--follow-symlinks')
fi

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^kernel.dmesg_restrict")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "1"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^kernel.dmesg_restrict\\>" "/etc/sysctl.conf"; then
    "${sed_command[@]}" "s/^kernel.dmesg_restrict\\>.*/$formatted_output/gi" "/etc/sysctl.conf"
else
    # \n is precaution for case where file ends without trailing newline
    
    printf '%s\n' "$formatted_output" >> "/etc/sysctl.conf"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: List /etc/sysctl.d/*.conf files
  find:
    paths: /etc/sysctl.d/
    contains: ^[\s]*kernel.dmesg_restrict.*$
    patterns: '*.conf'
  register: find_sysctl_d
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-171-3.1.5
    - NIST-800-53-SI-11(a)
    - NIST-800-53-SI-11(b)
    - disable_strategy
    - low_complexity
    - low_severity
    - medium_disruption
    - reboot_required
    - sysctl_kernel_dmesg_restrict

- name: Comment out any occurrences of kernel.dmesg_restrict from /etc/sysctl.d/*.conf
    files
  replace:
    path: '{{ item }}'
    regexp: ^[\s]*kernel.dmesg_restrict
    replace: '#kernel.dmesg_restrict'
  loop: '{{ find_sysctl_d.files }}'
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-171-3.1.5
    - NIST-800-53-SI-11(a)
    - NIST-800-53-SI-11(b)
    - disable_strategy
    - low_complexity
    - low_severity
    - medium_disruption
    - reboot_required
    - sysctl_kernel_dmesg_restrict

- name: Ensure sysctl kernel.dmesg_restrict is set to 1
  sysctl:
    name: kernel.dmesg_restrict
    value: '1'
    state: present
    reload: true
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-171-3.1.5
    - NIST-800-53-SI-11(a)
    - NIST-800-53-SI-11(b)
    - disable_strategy
    - low_complexity
    - low_severity
    - medium_disruption
    - reboot_required
    - sysctl_kernel_dmesg_restrict

---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,kernel.dmesg_restrict%3D1%0A
        mode: 0644
        path: /etc/sysctl.d/75-sysctl_kernel_dmesg_restrict.conf
        overwrite: true
OVAL test results details

kernel.dmesg_restrict static configuration  oval:ssg-test_static_sysctl_kernel_dmesg_restrict:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_sysctl_kernel_dmesg_restrict:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/sysctl.conf^[\s]*kernel.dmesg_restrict[\s]*=[\s]*1[\s]*$1

kernel.dmesg_restrict static configuration in /etc/sysctl.d/*.conf  oval:ssg-test_static_etc_sysctld_kernel_dmesg_restrict:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_etc_sysctld_kernel_dmesg_restrict:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/etc/sysctl.d^.*\.conf$^[\s]*kernel.dmesg_restrict[\s]*=[\s]*1[\s]*$1

kernel.dmesg_restrict static configuration in /etc/sysctl.d/*.conf  oval:ssg-test_static_run_sysctld_kernel_dmesg_restrict:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_run_sysctld_kernel_dmesg_restrict:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/run/sysctl.d^.*\.conf$^[\s]*kernel.dmesg_restrict[\s]*=[\s]*1[\s]*$1

kernel.dmesg_restrict static configuration in /etc/sysctl.d/*.conf  oval:ssg-test_static_usr_lib_sysctld_kernel_dmesg_restrict:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_usr_lib_sysctld_kernel_dmesg_restrict:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/usr/lib/sysctl.d^.*\.conf$^[\s]*kernel.dmesg_restrict[\s]*=[\s]*1[\s]*$1

kernel runtime parameter kernel.dmesg_restrict set to 1  oval:ssg-test_sysctl_runtime_kernel_dmesg_restrict:tst:1  false

Following items have been found on the system:
NameValue
kernel.dmesg_restrict0
Disable Kernel Image Loadingxccdf_org.ssgproject.content_rule_sysctl_kernel_kexec_load_disabled medium

Disable Kernel Image Loading

Rule IDxccdf_org.ssgproject.content_rule_sysctl_kernel_kexec_load_disabled
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-sysctl_kernel_kexec_load_disabled:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-001749, CM-6, SRG-OS-000480-GPOS-00227, SRG-OS-000366-GPOS-00153

Description
To set the runtime status of the kernel.kexec_load_disabled kernel parameter, run the following command:
$ sudo sysctl -w kernel.kexec_load_disabled=1
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
kernel.kexec_load_disabled = 1
Rationale
Disabling kexec_load allows greater control of the kernel memory. It makes it impossible to load another kernel image after it has been disabled.

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

# Comment out any occurrences of kernel.kexec_load_disabled from /etc/sysctl.d/*.conf files
for f in /etc/sysctl.d/*.conf ; do
  matching_list=$(grep -P '^(?!#).*[\s]+kernel.kexec_load_disabled.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      # comment out "kernel.kexec_load_disabled" matches to preserve user data
      sed -i "s/^${entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

#
# Set runtime for kernel.kexec_load_disabled
#
/sbin/sysctl -q -n -w kernel.kexec_load_disabled="1"

#
# If kernel.kexec_load_disabled present in /etc/sysctl.conf, change value to "1"
#	else, add "kernel.kexec_load_disabled = 1" to /etc/sysctl.conf
#
# Test if the config_file is a symbolic link. If so, use --follow-symlinks with sed.
# Otherwise, regular sed command will do.
sed_command=('sed' '-i')
if test -L "/etc/sysctl.conf"; then
    sed_command+=('--follow-symlinks')
fi

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^kernel.kexec_load_disabled")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "1"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^kernel.kexec_load_disabled\\>" "/etc/sysctl.conf"; then
    "${sed_command[@]}" "s/^kernel.kexec_load_disabled\\>.*/$formatted_output/gi" "/etc/sysctl.conf"
else
    # \n is precaution for case where file ends without trailing newline
    
    printf '%s\n' "$formatted_output" >> "/etc/sysctl.conf"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: List /etc/sysctl.d/*.conf files
  find:
    paths: /etc/sysctl.d/
    contains: ^[\s]*kernel.kexec_load_disabled.*$
    patterns: '*.conf'
  register: find_sysctl_d
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-CM-6
    - disable_strategy
    - low_complexity
    - medium_disruption
    - medium_severity
    - reboot_required
    - sysctl_kernel_kexec_load_disabled

- name: Comment out any occurrences of kernel.kexec_load_disabled from /etc/sysctl.d/*.conf
    files
  replace:
    path: '{{ item }}'
    regexp: ^[\s]*kernel.kexec_load_disabled
    replace: '#kernel.kexec_load_disabled'
  loop: '{{ find_sysctl_d.files }}'
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-CM-6
    - disable_strategy
    - low_complexity
    - medium_disruption
    - medium_severity
    - reboot_required
    - sysctl_kernel_kexec_load_disabled

- name: Ensure sysctl kernel.kexec_load_disabled is set to 1
  sysctl:
    name: kernel.kexec_load_disabled
    value: '1'
    state: present
    reload: true
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-CM-6
    - disable_strategy
    - low_complexity
    - medium_disruption
    - medium_severity
    - reboot_required
    - sysctl_kernel_kexec_load_disabled

---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,kernel.kexec_load_disabled%3D1%0A
        mode: 0644
        path: /etc/sysctl.d/75-sysctl_kernel_kexec_load_disabled.conf
        overwrite: true
OVAL test results details

kernel.kexec_load_disabled static configuration  oval:ssg-test_static_sysctl_kernel_kexec_load_disabled:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_sysctl_kernel_kexec_load_disabled:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/sysctl.conf^[\s]*kernel.kexec_load_disabled[\s]*=[\s]*1[\s]*$1

kernel.kexec_load_disabled static configuration in /etc/sysctl.d/*.conf  oval:ssg-test_static_etc_sysctld_kernel_kexec_load_disabled:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_etc_sysctld_kernel_kexec_load_disabled:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/etc/sysctl.d^.*\.conf$^[\s]*kernel.kexec_load_disabled[\s]*=[\s]*1[\s]*$1

kernel.kexec_load_disabled static configuration in /etc/sysctl.d/*.conf  oval:ssg-test_static_run_sysctld_kernel_kexec_load_disabled:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_run_sysctld_kernel_kexec_load_disabled:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/run/sysctl.d^.*\.conf$^[\s]*kernel.kexec_load_disabled[\s]*=[\s]*1[\s]*$1

kernel.kexec_load_disabled static configuration in /etc/sysctl.d/*.conf  oval:ssg-test_static_usr_lib_sysctld_kernel_kexec_load_disabled:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_usr_lib_sysctld_kernel_kexec_load_disabled:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/usr/lib/sysctl.d^.*\.conf$^[\s]*kernel.kexec_load_disabled[\s]*=[\s]*1[\s]*$1

kernel runtime parameter kernel.kexec_load_disabled set to 1  oval:ssg-test_sysctl_runtime_kernel_kexec_load_disabled:tst:1  false

Following items have been found on the system:
NameValue
kernel.kexec_load_disabled0
Disallow kernel profiling by unprivileged usersxccdf_org.ssgproject.content_rule_sysctl_kernel_perf_event_paranoid low

Disallow kernel profiling by unprivileged users

Rule IDxccdf_org.ssgproject.content_rule_sysctl_kernel_perf_event_paranoid
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-sysctl_kernel_perf_event_paranoid:def:1
Time2024-12-29T17:33:55+01:00
Severitylow
Identifiers and References

References:  BP28(R23), CCI-001090, AC-6, FMT_SMF_EXT.1, SRG-OS-000132-GPOS-00067, SRG-OS-000138-GPOS-00069

Description
To set the runtime status of the kernel.perf_event_paranoid kernel parameter, run the following command:
$ sudo sysctl -w kernel.perf_event_paranoid=2
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
kernel.perf_event_paranoid = 2
Rationale
Kernel profiling can reveal sensitive information about kernel behaviour.

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

# Comment out any occurrences of kernel.perf_event_paranoid from /etc/sysctl.d/*.conf files
for f in /etc/sysctl.d/*.conf ; do
  matching_list=$(grep -P '^(?!#).*[\s]+kernel.perf_event_paranoid.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      # comment out "kernel.perf_event_paranoid" matches to preserve user data
      sed -i "s/^${entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

#
# Set runtime for kernel.perf_event_paranoid
#
/sbin/sysctl -q -n -w kernel.perf_event_paranoid="2"

#
# If kernel.perf_event_paranoid present in /etc/sysctl.conf, change value to "2"
#	else, add "kernel.perf_event_paranoid = 2" to /etc/sysctl.conf
#
# Test if the config_file is a symbolic link. If so, use --follow-symlinks with sed.
# Otherwise, regular sed command will do.
sed_command=('sed' '-i')
if test -L "/etc/sysctl.conf"; then
    sed_command+=('--follow-symlinks')
fi

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^kernel.perf_event_paranoid")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "2"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^kernel.perf_event_paranoid\\>" "/etc/sysctl.conf"; then
    "${sed_command[@]}" "s/^kernel.perf_event_paranoid\\>.*/$formatted_output/gi" "/etc/sysctl.conf"
else
    # \n is precaution for case where file ends without trailing newline
    
    printf '%s\n' "$formatted_output" >> "/etc/sysctl.conf"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: List /etc/sysctl.d/*.conf files
  find:
    paths: /etc/sysctl.d/
    contains: ^[\s]*kernel.perf_event_paranoid.*$
    patterns: '*.conf'
  register: find_sysctl_d
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-AC-6
    - disable_strategy
    - low_complexity
    - low_severity
    - medium_disruption
    - reboot_required
    - sysctl_kernel_perf_event_paranoid

- name: Comment out any occurrences of kernel.perf_event_paranoid from /etc/sysctl.d/*.conf
    files
  replace:
    path: '{{ item }}'
    regexp: ^[\s]*kernel.perf_event_paranoid
    replace: '#kernel.perf_event_paranoid'
  loop: '{{ find_sysctl_d.files }}'
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-AC-6
    - disable_strategy
    - low_complexity
    - low_severity
    - medium_disruption
    - reboot_required
    - sysctl_kernel_perf_event_paranoid

- name: Ensure sysctl kernel.perf_event_paranoid is set to 2
  sysctl:
    name: kernel.perf_event_paranoid
    value: '2'
    state: present
    reload: true
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-AC-6
    - disable_strategy
    - low_complexity
    - low_severity
    - medium_disruption
    - reboot_required
    - sysctl_kernel_perf_event_paranoid

---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,kernel.perf_event_paranoid%3D2%0A
        mode: 0644
        path: /etc/sysctl.d/75-sysctl_kernel_perf_event_paranoid.conf
        overwrite: true
OVAL test results details

kernel.perf_event_paranoid static configuration  oval:ssg-test_static_sysctl_kernel_perf_event_paranoid:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_sysctl_kernel_perf_event_paranoid:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/sysctl.conf^[\s]*kernel.perf_event_paranoid[\s]*=[\s]*2[\s]*$1

kernel.perf_event_paranoid static configuration in /etc/sysctl.d/*.conf  oval:ssg-test_static_etc_sysctld_kernel_perf_event_paranoid:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_etc_sysctld_kernel_perf_event_paranoid:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/etc/sysctl.d^.*\.conf$^[\s]*kernel.perf_event_paranoid[\s]*=[\s]*2[\s]*$1

kernel.perf_event_paranoid static configuration in /etc/sysctl.d/*.conf  oval:ssg-test_static_run_sysctld_kernel_perf_event_paranoid:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_run_sysctld_kernel_perf_event_paranoid:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/run/sysctl.d^.*\.conf$^[\s]*kernel.perf_event_paranoid[\s]*=[\s]*2[\s]*$1

kernel.perf_event_paranoid static configuration in /etc/sysctl.d/*.conf  oval:ssg-test_static_usr_lib_sysctld_kernel_perf_event_paranoid:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_usr_lib_sysctld_kernel_perf_event_paranoid:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/usr/lib/sysctl.d^.*\.conf$^[\s]*kernel.perf_event_paranoid[\s]*=[\s]*2[\s]*$1

kernel runtime parameter kernel.perf_event_paranoid set to 2  oval:ssg-test_sysctl_runtime_kernel_perf_event_paranoid:tst:1  true

Following items have been found on the system:
NameValue
kernel.perf_event_paranoid2
Disable Access to Network bpf() Syscall From Unprivileged Processesxccdf_org.ssgproject.content_rule_sysctl_kernel_unprivileged_bpf_disabled medium

Disable Access to Network bpf() Syscall From Unprivileged Processes

Rule IDxccdf_org.ssgproject.content_rule_sysctl_kernel_unprivileged_bpf_disabled
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-sysctl_kernel_unprivileged_bpf_disabled:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-000366, AC-6, SC-7(10), FMT_SMF_EXT.1, SRG-OS-000132-GPOS-00067, SRG-OS-000480-GPOS-00227

Description
To set the runtime status of the kernel.unprivileged_bpf_disabled kernel parameter, run the following command:
$ sudo sysctl -w kernel.unprivileged_bpf_disabled=1
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
kernel.unprivileged_bpf_disabled = 1
Rationale
Loading and accessing the packet filters programs and maps using the bpf() syscall has the potential of revealing sensitive information about the kernel state.

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

# Comment out any occurrences of kernel.unprivileged_bpf_disabled from /etc/sysctl.d/*.conf files
for f in /etc/sysctl.d/*.conf ; do
  matching_list=$(grep -P '^(?!#).*[\s]+kernel.unprivileged_bpf_disabled.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      # comment out "kernel.unprivileged_bpf_disabled" matches to preserve user data
      sed -i "s/^${entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

#
# Set runtime for kernel.unprivileged_bpf_disabled
#
/sbin/sysctl -q -n -w kernel.unprivileged_bpf_disabled="1"

#
# If kernel.unprivileged_bpf_disabled present in /etc/sysctl.conf, change value to "1"
#	else, add "kernel.unprivileged_bpf_disabled = 1" to /etc/sysctl.conf
#
# Test if the config_file is a symbolic link. If so, use --follow-symlinks with sed.
# Otherwise, regular sed command will do.
sed_command=('sed' '-i')
if test -L "/etc/sysctl.conf"; then
    sed_command+=('--follow-symlinks')
fi

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^kernel.unprivileged_bpf_disabled")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "1"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^kernel.unprivileged_bpf_disabled\\>" "/etc/sysctl.conf"; then
    "${sed_command[@]}" "s/^kernel.unprivileged_bpf_disabled\\>.*/$formatted_output/gi" "/etc/sysctl.conf"
else
    # \n is precaution for case where file ends without trailing newline
    
    printf '%s\n' "$formatted_output" >> "/etc/sysctl.conf"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: List /etc/sysctl.d/*.conf files
  find:
    paths: /etc/sysctl.d/
    contains: ^[\s]*kernel.unprivileged_bpf_disabled.*$
    patterns: '*.conf'
  register: find_sysctl_d
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-AC-6
    - NIST-800-53-SC-7(10)
    - disable_strategy
    - low_complexity
    - medium_disruption
    - medium_severity
    - reboot_required
    - sysctl_kernel_unprivileged_bpf_disabled

- name: Comment out any occurrences of kernel.unprivileged_bpf_disabled from /etc/sysctl.d/*.conf
    files
  replace:
    path: '{{ item }}'
    regexp: ^[\s]*kernel.unprivileged_bpf_disabled
    replace: '#kernel.unprivileged_bpf_disabled'
  loop: '{{ find_sysctl_d.files }}'
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-AC-6
    - NIST-800-53-SC-7(10)
    - disable_strategy
    - low_complexity
    - medium_disruption
    - medium_severity
    - reboot_required
    - sysctl_kernel_unprivileged_bpf_disabled

- name: Ensure sysctl kernel.unprivileged_bpf_disabled is set to 1
  sysctl:
    name: kernel.unprivileged_bpf_disabled
    value: '1'
    state: present
    reload: true
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-AC-6
    - NIST-800-53-SC-7(10)
    - disable_strategy
    - low_complexity
    - medium_disruption
    - medium_severity
    - reboot_required
    - sysctl_kernel_unprivileged_bpf_disabled

---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,kernel.unprivileged_bpf_disabled%3D1%0A
        mode: 0644
        path: /etc/sysctl.d/75-sysctl_kernel_unprivileged_bpf_disabled.conf
        overwrite: true
OVAL test results details

kernel.unprivileged_bpf_disabled static configuration  oval:ssg-test_static_sysctl_kernel_unprivileged_bpf_disabled:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_sysctl_kernel_unprivileged_bpf_disabled:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/sysctl.conf^[\s]*kernel.unprivileged_bpf_disabled[\s]*=[\s]*1[\s]*$1

kernel.unprivileged_bpf_disabled static configuration in /etc/sysctl.d/*.conf  oval:ssg-test_static_etc_sysctld_kernel_unprivileged_bpf_disabled:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_etc_sysctld_kernel_unprivileged_bpf_disabled:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/etc/sysctl.d^.*\.conf$^[\s]*kernel.unprivileged_bpf_disabled[\s]*=[\s]*1[\s]*$1

kernel.unprivileged_bpf_disabled static configuration in /etc/sysctl.d/*.conf  oval:ssg-test_static_run_sysctld_kernel_unprivileged_bpf_disabled:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_run_sysctld_kernel_unprivileged_bpf_disabled:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/run/sysctl.d^.*\.conf$^[\s]*kernel.unprivileged_bpf_disabled[\s]*=[\s]*1[\s]*$1

kernel.unprivileged_bpf_disabled static configuration in /etc/sysctl.d/*.conf  oval:ssg-test_static_usr_lib_sysctld_kernel_unprivileged_bpf_disabled:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_usr_lib_sysctld_kernel_unprivileged_bpf_disabled:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/usr/lib/sysctl.d^.*\.conf$^[\s]*kernel.unprivileged_bpf_disabled[\s]*=[\s]*1[\s]*$1

kernel runtime parameter kernel.unprivileged_bpf_disabled set to 1  oval:ssg-test_sysctl_runtime_kernel_unprivileged_bpf_disabled:tst:1  false

Following items have been found on the system:
NameValue
kernel.unprivileged_bpf_disabled0
Restrict usage of ptrace to descendant processesxccdf_org.ssgproject.content_rule_sysctl_kernel_yama_ptrace_scope medium

Restrict usage of ptrace to descendant processes

Rule IDxccdf_org.ssgproject.content_rule_sysctl_kernel_yama_ptrace_scope
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-sysctl_kernel_yama_ptrace_scope:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  BP28(R25), CCI-000366, SC-7(10), SRG-OS-000132-GPOS-00067, SRG-OS-000480-GPOS-00227

Description
To set the runtime status of the kernel.yama.ptrace_scope kernel parameter, run the following command:
$ sudo sysctl -w kernel.yama.ptrace_scope=1
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
kernel.yama.ptrace_scope = 1
Rationale
Unrestricted usage of ptrace allows compromised binaries to run ptrace on another processes of the user. Like this, the attacker can steal sensitive information from the target processes (e.g. SSH sessions, web browser, ...) without any additional assistance from the user (i.e. without resorting to phishing).

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

# Comment out any occurrences of kernel.yama.ptrace_scope from /etc/sysctl.d/*.conf files
for f in /etc/sysctl.d/*.conf ; do
  matching_list=$(grep -P '^(?!#).*[\s]+kernel.yama.ptrace_scope.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      # comment out "kernel.yama.ptrace_scope" matches to preserve user data
      sed -i "s/^${entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

#
# Set runtime for kernel.yama.ptrace_scope
#
/sbin/sysctl -q -n -w kernel.yama.ptrace_scope="1"

#
# If kernel.yama.ptrace_scope present in /etc/sysctl.conf, change value to "1"
#	else, add "kernel.yama.ptrace_scope = 1" to /etc/sysctl.conf
#
# Test if the config_file is a symbolic link. If so, use --follow-symlinks with sed.
# Otherwise, regular sed command will do.
sed_command=('sed' '-i')
if test -L "/etc/sysctl.conf"; then
    sed_command+=('--follow-symlinks')
fi

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^kernel.yama.ptrace_scope")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "1"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^kernel.yama.ptrace_scope\\>" "/etc/sysctl.conf"; then
    "${sed_command[@]}" "s/^kernel.yama.ptrace_scope\\>.*/$formatted_output/gi" "/etc/sysctl.conf"
else
    # \n is precaution for case where file ends without trailing newline
    
    printf '%s\n' "$formatted_output" >> "/etc/sysctl.conf"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: List /etc/sysctl.d/*.conf files
  find:
    paths: /etc/sysctl.d/
    contains: ^[\s]*kernel.yama.ptrace_scope.*$
    patterns: '*.conf'
  register: find_sysctl_d
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-SC-7(10)
    - disable_strategy
    - low_complexity
    - medium_disruption
    - medium_severity
    - reboot_required
    - sysctl_kernel_yama_ptrace_scope

- name: Comment out any occurrences of kernel.yama.ptrace_scope from /etc/sysctl.d/*.conf
    files
  replace:
    path: '{{ item }}'
    regexp: ^[\s]*kernel.yama.ptrace_scope
    replace: '#kernel.yama.ptrace_scope'
  loop: '{{ find_sysctl_d.files }}'
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-SC-7(10)
    - disable_strategy
    - low_complexity
    - medium_disruption
    - medium_severity
    - reboot_required
    - sysctl_kernel_yama_ptrace_scope

- name: Ensure sysctl kernel.yama.ptrace_scope is set to 1
  sysctl:
    name: kernel.yama.ptrace_scope
    value: '1'
    state: present
    reload: true
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-SC-7(10)
    - disable_strategy
    - low_complexity
    - medium_disruption
    - medium_severity
    - reboot_required
    - sysctl_kernel_yama_ptrace_scope

---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,kernel.yama.ptrace_scope%3D1%0A
        mode: 0644
        path: /etc/sysctl.d/75-sysctl_kernel_yama_ptrace_scope.conf
        overwrite: true
OVAL test results details

kernel.yama.ptrace_scope static configuration  oval:ssg-test_static_sysctl_kernel_yama_ptrace_scope:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_sysctl_kernel_yama_ptrace_scope:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/sysctl.conf^[\s]*kernel.yama.ptrace_scope[\s]*=[\s]*1[\s]*$1

kernel.yama.ptrace_scope static configuration in /etc/sysctl.d/*.conf  oval:ssg-test_static_etc_sysctld_kernel_yama_ptrace_scope:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_etc_sysctld_kernel_yama_ptrace_scope:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/etc/sysctl.d^.*\.conf$^[\s]*kernel.yama.ptrace_scope[\s]*=[\s]*1[\s]*$1

kernel.yama.ptrace_scope static configuration in /etc/sysctl.d/*.conf  oval:ssg-test_static_run_sysctld_kernel_yama_ptrace_scope:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_run_sysctld_kernel_yama_ptrace_scope:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/run/sysctl.d^.*\.conf$^[\s]*kernel.yama.ptrace_scope[\s]*=[\s]*1[\s]*$1

kernel.yama.ptrace_scope static configuration in /etc/sysctl.d/*.conf  oval:ssg-test_static_usr_lib_sysctld_kernel_yama_ptrace_scope:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_usr_lib_sysctld_kernel_yama_ptrace_scope:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/usr/lib/sysctl.d^.*\.conf$^[\s]*kernel.yama.ptrace_scope[\s]*=[\s]*1[\s]*$1

kernel runtime parameter kernel.yama.ptrace_scope set to 1  oval:ssg-test_sysctl_runtime_kernel_yama_ptrace_scope:tst:1  false

Following items have been found on the system:
NameValue
kernel.yama.ptrace_scope0
Harden the operation of the BPF just-in-time compilerxccdf_org.ssgproject.content_rule_sysctl_net_core_bpf_jit_harden medium

Harden the operation of the BPF just-in-time compiler

Rule IDxccdf_org.ssgproject.content_rule_sysctl_net_core_bpf_jit_harden
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-sysctl_net_core_bpf_jit_harden:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-000366, CM-6, SC-7(10), FMT_SMF_EXT.1, SRG-OS-000480-GPOS-00227

Description
To set the runtime status of the net.core.bpf_jit_harden kernel parameter, run the following command:
$ sudo sysctl -w net.core.bpf_jit_harden=2
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.core.bpf_jit_harden = 2
Rationale
When hardened, the extended Berkeley Packet Filter just-in-time compiler will randomize any kernel addresses in the BPF programs and maps, and will not expose the JIT addresses in /proc/kallsyms.

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

# Comment out any occurrences of net.core.bpf_jit_harden from /etc/sysctl.d/*.conf files
for f in /etc/sysctl.d/*.conf ; do
  matching_list=$(grep -P '^(?!#).*[\s]+net.core.bpf_jit_harden.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      # comment out "net.core.bpf_jit_harden" matches to preserve user data
      sed -i "s/^${entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

#
# Set runtime for net.core.bpf_jit_harden
#
/sbin/sysctl -q -n -w net.core.bpf_jit_harden="2"

#
# If net.core.bpf_jit_harden present in /etc/sysctl.conf, change value to "2"
#	else, add "net.core.bpf_jit_harden = 2" to /etc/sysctl.conf
#
# Test if the config_file is a symbolic link. If so, use --follow-symlinks with sed.
# Otherwise, regular sed command will do.
sed_command=('sed' '-i')
if test -L "/etc/sysctl.conf"; then
    sed_command+=('--follow-symlinks')
fi

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^net.core.bpf_jit_harden")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "2"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^net.core.bpf_jit_harden\\>" "/etc/sysctl.conf"; then
    "${sed_command[@]}" "s/^net.core.bpf_jit_harden\\>.*/$formatted_output/gi" "/etc/sysctl.conf"
else
    # \n is precaution for case where file ends without trailing newline
    
    printf '%s\n' "$formatted_output" >> "/etc/sysctl.conf"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: List /etc/sysctl.d/*.conf files
  find:
    paths: /etc/sysctl.d/
    contains: ^[\s]*net.core.bpf_jit_harden.*$
    patterns: '*.conf'
  register: find_sysctl_d
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-CM-6
    - NIST-800-53-SC-7(10)
    - disable_strategy
    - low_complexity
    - medium_disruption
    - medium_severity
    - reboot_required
    - sysctl_net_core_bpf_jit_harden

- name: Comment out any occurrences of net.core.bpf_jit_harden from /etc/sysctl.d/*.conf
    files
  replace:
    path: '{{ item }}'
    regexp: ^[\s]*net.core.bpf_jit_harden
    replace: '#net.core.bpf_jit_harden'
  loop: '{{ find_sysctl_d.files }}'
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-CM-6
    - NIST-800-53-SC-7(10)
    - disable_strategy
    - low_complexity
    - medium_disruption
    - medium_severity
    - reboot_required
    - sysctl_net_core_bpf_jit_harden

- name: Ensure sysctl net.core.bpf_jit_harden is set to 2
  sysctl:
    name: net.core.bpf_jit_harden
    value: '2'
    state: present
    reload: true
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-CM-6
    - NIST-800-53-SC-7(10)
    - disable_strategy
    - low_complexity
    - medium_disruption
    - medium_severity
    - reboot_required
    - sysctl_net_core_bpf_jit_harden

---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,net.core.bpf_jit_harden%3D2%0A
        mode: 0644
        path: /etc/sysctl.d/75-sysctl_net_core_bpf_jit_harden.conf
        overwrite: true
OVAL test results details

net.core.bpf_jit_harden static configuration  oval:ssg-test_static_sysctl_net_core_bpf_jit_harden:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_sysctl_net_core_bpf_jit_harden:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/sysctl.conf^[\s]*net.core.bpf_jit_harden[\s]*=[\s]*2[\s]*$1

net.core.bpf_jit_harden static configuration in /etc/sysctl.d/*.conf  oval:ssg-test_static_etc_sysctld_net_core_bpf_jit_harden:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_etc_sysctld_net_core_bpf_jit_harden:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/etc/sysctl.d^.*\.conf$^[\s]*net.core.bpf_jit_harden[\s]*=[\s]*2[\s]*$1

net.core.bpf_jit_harden static configuration in /etc/sysctl.d/*.conf  oval:ssg-test_static_run_sysctld_net_core_bpf_jit_harden:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_run_sysctld_net_core_bpf_jit_harden:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/run/sysctl.d^.*\.conf$^[\s]*net.core.bpf_jit_harden[\s]*=[\s]*2[\s]*$1

net.core.bpf_jit_harden static configuration in /etc/sysctl.d/*.conf  oval:ssg-test_static_usr_lib_sysctld_net_core_bpf_jit_harden:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_usr_lib_sysctld_net_core_bpf_jit_harden:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/usr/lib/sysctl.d^.*\.conf$^[\s]*net.core.bpf_jit_harden[\s]*=[\s]*2[\s]*$1

kernel runtime parameter net.core.bpf_jit_harden set to 2  oval:ssg-test_sysctl_runtime_net_core_bpf_jit_harden:tst:1  false

Following items have been found on the system:
NameValue
net.core.bpf_jit_harden0
Disable the use of user namespacesxccdf_org.ssgproject.content_rule_sysctl_user_max_user_namespaces medium

Disable the use of user namespaces

Rule IDxccdf_org.ssgproject.content_rule_sysctl_user_max_user_namespaces
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-sysctl_user_max_user_namespaces:def:1
Time2024-12-29T17:33:55+01:00
Severitymedium
Identifiers and References

References:  CCI-000366, SC-39, CM-6(a), FMT_SMF_EXT.1, SRG-OS-000480-GPOS-00227

Description
To set the runtime status of the user.max_user_namespaces kernel parameter, run the following command:
$ sudo sysctl -w user.max_user_namespaces=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
user.max_user_namespaces = 0
When containers are deployed on the machine, the value should be set to large non-zero value.
Rationale
User namespaces are used primarily for Linux containers. The value 0 disallows the use of user namespaces.
Warnings
warning  This configuration baseline was created to deploy the base operating system for general purpose workloads. When the operating system is configured for certain purposes, such as to host Linux Containers, it is expected that user.max_user_namespaces will be enabled.

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

# Comment out any occurrences of user.max_user_namespaces from /etc/sysctl.d/*.conf files
for f in /etc/sysctl.d/*.conf ; do
  matching_list=$(grep -P '^(?!#).*[\s]+user.max_user_namespaces.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      # comment out "user.max_user_namespaces" matches to preserve user data
      sed -i "s/^${entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

#
# Set runtime for user.max_user_namespaces
#
/sbin/sysctl -q -n -w user.max_user_namespaces="0"

#
# If user.max_user_namespaces present in /etc/sysctl.conf, change value to "0"
#	else, add "user.max_user_namespaces = 0" to /etc/sysctl.conf
#
# Test if the config_file is a symbolic link. If so, use --follow-symlinks with sed.
# Otherwise, regular sed command will do.
sed_command=('sed' '-i')
if test -L "/etc/sysctl.conf"; then
    sed_command+=('--follow-symlinks')
fi

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^user.max_user_namespaces")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "0"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^user.max_user_namespaces\\>" "/etc/sysctl.conf"; then
    "${sed_command[@]}" "s/^user.max_user_namespaces\\>.*/$formatted_output/gi" "/etc/sysctl.conf"
else
    # \n is precaution for case where file ends without trailing newline
    
    printf '%s\n' "$formatted_output" >> "/etc/sysctl.conf"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: List /etc/sysctl.d/*.conf files
  find:
    paths: /etc/sysctl.d/
    contains: ^[\s]*user.max_user_namespaces.*$
    patterns: '*.conf'
  register: find_sysctl_d
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-CM-6(a)
    - NIST-800-53-SC-39
    - disable_strategy
    - low_complexity
    - medium_disruption
    - medium_severity
    - reboot_required
    - sysctl_user_max_user_namespaces

- name: Comment out any occurrences of user.max_user_namespaces from /etc/sysctl.d/*.conf
    files
  replace:
    path: '{{ item }}'
    regexp: ^[\s]*user.max_user_namespaces
    replace: '#user.max_user_namespaces'
  loop: '{{ find_sysctl_d.files }}'
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-CM-6(a)
    - NIST-800-53-SC-39
    - disable_strategy
    - low_complexity
    - medium_disruption
    - medium_severity
    - reboot_required
    - sysctl_user_max_user_namespaces

- name: Ensure sysctl user.max_user_namespaces is set to 0
  sysctl:
    name: user.max_user_namespaces
    value: '0'
    state: present
    reload: true
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-CM-6(a)
    - NIST-800-53-SC-39
    - disable_strategy
    - low_complexity
    - medium_disruption
    - medium_severity
    - reboot_required
    - sysctl_user_max_user_namespaces

---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,user.max_user_namespaces%20%3D%200%0A
        mode: 0644
        path: /etc/sysctl.d/75-sysctl_user_max_user_namespaces.conf
        overwrite: true
OVAL test results details

user.max_user_namespaces static configuration  oval:ssg-test_static_sysctl_user_max_user_namespaces:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_sysctl_user_max_user_namespaces:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/sysctl.conf^[\s]*user.max_user_namespaces[\s]*=[\s]*0[\s]*$1

user.max_user_namespaces static configuration in /etc/sysctl.d/*.conf  oval:ssg-test_static_etc_sysctld_user_max_user_namespaces:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_etc_sysctld_user_max_user_namespaces:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/etc/sysctl.d^.*\.conf$^[\s]*user.max_user_namespaces[\s]*=[\s]*0[\s]*$1

user.max_user_namespaces static configuration in /etc/sysctl.d/*.conf  oval:ssg-test_static_run_sysctld_user_max_user_namespaces:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_run_sysctld_user_max_user_namespaces:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/run/sysctl.d^.*\.conf$^[\s]*user.max_user_namespaces[\s]*=[\s]*0[\s]*$1

user.max_user_namespaces static configuration in /etc/sysctl.d/*.conf  oval:ssg-test_static_usr_lib_sysctld_user_max_user_namespaces:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-object_static_usr_lib_sysctld_user_max_user_namespaces:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/usr/lib/sysctl.d^.*\.conf$^[\s]*user.max_user_namespaces[\s]*=[\s]*0[\s]*$1

kernel runtime parameter user.max_user_namespaces set to 0  oval:ssg-test_sysctl_runtime_user_max_user_namespaces:tst:1  false

Following items have been found on the system:
NameValue
user.max_user_namespaces31650
Ensure No Device Files are Unlabeled by SELinuxxccdf_org.ssgproject.content_rule_selinux_all_devicefiles_labeled medium

Ensure No Device Files are Unlabeled by SELinux

Rule IDxccdf_org.ssgproject.content_rule_selinux_all_devicefiles_labeled
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-selinux_all_devicefiles_labeled:def:1
Time2024-12-29T17:33:56+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 18, 2, 3, 5, 6, 7, 8, 9, APO01.06, APO11.04, BAI01.06, BAI03.05, BAI06.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS06.02, DSS06.06, MEA02.01, 3.1.2, 3.1.5, 3.7.2, CCI-000022, CCI-000032, CCI-000318, CCI-000366, CCI-000368, CCI-001812, CCI-001813, CCI-001814, 4.3.3.3.9, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.3.2, 4.3.4.3.3, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.10, SR 2.11, SR 2.12, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 2.8, SR 2.9, SR 5.2, SR 6.2, SR 7.6, A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.12.1.2, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.5.1, A.12.6.2, A.12.7.1, A.13.1.1, A.13.1.3, A.13.2.1, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4, A.14.2.7, A.15.2.1, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5, CM-7(a), CM-7(b), CM-6(a), AC-3(3)(a), AC-6, DE.CM-1, DE.CM-7, PR.AC-4, PR.DS-5, PR.IP-1, PR.IP-3, PR.PT-1, PR.PT-3, SRG-OS-000480-GPOS-00227

Description
Device files, which are used for communication with important system resources, should be labeled with proper SELinux types. If any device files carry the SELinux type device_t or unlabeled_t, report the bug so that policy can be corrected. Supply information about what the device is and what programs use it.

To check for incorrectly labeled device files, run following commands:
$ sudo find /dev -context *:device_t:* \( -type c -o -type b \) -printf "%p %Z\n"
$ sudo find /dev -context *:unlabeled_t:* \( -type c -o -type b \) -printf "%p %Z\n"
It should produce no output in a well-configured system.
Rationale
If a device file carries the SELinux type device_t or unlabeled_t, then SELinux cannot properly restrict access to the device file.
Warnings
warning  Automatic remediation of this control is not available. The remediation can be achieved by amending SELinux policy.
OVAL test results details

device_t in /dev  oval:ssg-test_selinux_dev_device_t:tst:1  false

Following items have been found on the system:
FilepathPathFilenameUserRoleTypeLow sensitivityRawlow sensitivity
/dev/udmabuf/devudmabufsystem_uobject_rdevice_ts0s0
/dev/zram0/devzram0system_uobject_rdevice_ts0s0
/dev/dma_heap/system/dev/dma_heapsystemsystem_uobject_rdevice_ts0s0

unlabeled_t in /dev  oval:ssg-test_selinux_dev_unlabeled_t:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-object_selinux_dev_unlabeled_t:obj:1 of type selinuxsecuritycontext_object
FilepathFilter
/dev/vcsu6
/dev/vcs6
/dev/vcsa5
/dev/vcsu5
/dev/vcs5
/dev/vcsa4
/dev/vcsu4
/dev/tty54
/dev/tty53
/dev/tty52
/dev/tty51
/dev/tty50
/dev/tty49
/dev/tty48
/dev/tty47
/dev/tty46
/dev/tty45
/dev/tty44
/dev/tty43
/dev/tty42
/dev/tty41
/dev/tty40
/dev/tty39
/dev/tty38
/dev/tty37
/dev/tty36
/dev/tty35
/dev/tty34
/dev/tty33
/dev/tty32
/dev/tty31
/dev/tty30
/dev/tty29
/dev/tty28
/dev/tty27
/dev/tty26
/dev/tty25
/dev/tty24
/dev/tty23
/dev/tty22
/dev/tty21
/dev/tty20
/dev/tty19
/dev/tty18
/dev/tty17
/dev/tty16
/dev/tty15
/dev/tty14
/dev/tty13
/dev/tty12
/dev/tty11
/dev/tty10
/dev/tty9
/dev/tty8
/dev/tty7
/dev/tty6
/dev/tty5
/dev/tty4
/dev/tty3
/dev/tty2
/dev/tty1
/dev/vcsa1
/dev/vcsu1
/dev/vcs1
/dev/vcsa
/dev/vcsu
/dev/vcs
/dev/tty0
/dev/console
/dev/tty
/dev/kmsg
/dev/urandom
/dev/random
/dev/full
/dev/zero
/dev/port
/dev/null
/dev/mem
/dev/vga_arbiter
/dev/vcsa6
/dev/btrfs-control
/dev/cpu_dma_latency
/dev/mcelog
/dev/rtc0
/dev/input/event1
/dev/udmabuf
/dev/hwrng
/dev/nvram
/dev/hpet
/dev/ttyS31
/dev/ttyS30
/dev/ttyS29
/dev/ttyS28
/dev/ttyS27
/dev/ttyS26
/dev/ttyS25
/dev/ttyS24
/dev/ttyS23
/dev/ttyS22
/dev/ttyS21
/dev/ttyS20
/dev/ttyS19
/dev/ttyS18
/dev/ttyS17
/dev/ttyS16
/dev/ttyS15
/dev/ttyS14
/dev/ttyS13
/dev/ttyS12
/dev/ttyS11
/dev/ttyS10
/dev/ttyS9
/dev/ttyS8
/dev/ttyS7
/dev/ttyS6
/dev/ttyS5
/dev/ttyS4
/dev/ttyS3
/dev/ttyS2
/dev/ttyS1
/dev/ttyS0
/dev/ptmx
/dev/autofs
/dev/snapshot
/dev/cpu/3/cpuid
/dev/tty63
/dev/tty62
/dev/tty61
/dev/tty60
/dev/tty59
/dev/tty58
/dev/tty57
/dev/tty56
/dev/tty55
/dev/uhid
/dev/loop-control
/dev/pts/ptmx
/dev/sg1
/dev/sr0
/dev/sda2
/dev/sda1
/dev/bsg/1:0:0:0
/dev/sda
/dev/sg0
/dev/vcs4
/dev/fb0
/dev/vcsa3
/dev/vcsu3
/dev/vcs3
/dev/vcsa2
/dev/vcsu2
/dev/vcs2
/dev/vboxuser
/dev/uinput
/dev/ppp
/dev/net/tun
/dev/fuse
/dev/vboxguest
/dev/snd/seq
/dev/vhost-vsock
/dev/vhost-net
/dev/vhci
/dev/vfio/vfio
/dev/snd/timer
/dev/raw/rawctl
/dev/zram0
/dev/dm-0
/dev/dri/card0
/dev/dri/renderD128
/dev/rfkill
/dev/pts/0
/dev/bsg/0:0:0:0
/dev/mapper/control
/dev/cpu/2/cpuid
/dev/dma_heap/system
/dev/input/js0
/dev/input/event5
/dev/input/mouse1
/dev/input/event4
/dev/input/event3
/dev/input/mouse0
/dev/input/event2
/dev/input/event0
/dev/input/mice
/dev/usbmon0
/dev/cpu/1/cpuid
/dev/cpu/0/cpuid
/dev/cpu/3/msr
/dev/cpu/2/msr
/dev/cpu/1/msr
/dev/cpu/0/msr
oval:ssg-state_selinux_dev_unlabeled_t:ste:1
Ensure No Daemons are Unconfined by SELinuxxccdf_org.ssgproject.content_rule_selinux_confinement_of_daemons medium

Ensure No Daemons are Unconfined by SELinux

Rule IDxccdf_org.ssgproject.content_rule_selinux_confinement_of_daemons
Result
pass
Multi-check ruleno
OVAL Definition IDoval:ssg-selinux_confinement_of_daemons:def:1
Time2024-12-29T17:33:56+01:00
Severitymedium
Identifiers and References

References:  1, 11, 12, 13, 14, 15, 16, 18, 3, 5, 6, 9, APO01.06, APO11.04, BAI03.05, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS06.02, DSS06.06, MEA02.01, 3.1.2, 3.1.5, 3.7.2, 164.308(a)(1)(ii)(D), 164.308(a)(3), 164.308(a)(4), 164.310(b), 164.310(c), 164.312(a), 164.312(e), 4.3.3.3.9, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.3.2, 4.3.4.3.3, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.10, SR 2.11, SR 2.12, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 2.8, SR 2.9, SR 5.2, SR 7.6, A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.12.1.2, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.5.1, A.12.6.2, A.12.7.1, A.13.1.1, A.13.1.3, A.13.2.1, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5, CIP-003-8 R5.1.1, CIP-003-8 R5.3, CIP-004-6 R2.3, CIP-007-3 R2.1, CIP-007-3 R2.2, CIP-007-3 R2.3, CIP-007-3 R5.1, CIP-007-3 R5.1.1, CIP-007-3 R5.1.2, CM-7(a), CM-7(b), CM-6(a), AC-3(3)(a), AC-6, PR.AC-4, PR.DS-5, PR.IP-1, PR.PT-1, PR.PT-3

Description
Daemons for which the SELinux policy does not contain rules will inherit the context of the parent process. Because daemons are launched during startup and descend from the init process, they inherit the unconfined_service_t context.

To check for unconfined daemons, run the following command:
$ sudo ps -eZ | grep "unconfined_service_t"
It should produce no output in a well-configured system.
Rationale
Daemons which run with the unconfined_service_t context may cause AVC denials, or allow privileges that the daemon does not require.
Warnings
warning  Automatic remediation of this control is not available. Remediation can be achieved by amending SELinux policy or stopping the unconfined daemons as outlined above.
OVAL test results details

none satisfy unconfined_service_t in /proc  oval:ssg-test_selinux_confinement_of_daemons:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-object_selinux_confinement_of_daemons:obj:1 of type selinuxsecuritycontext_object
BehaviorsPathFilenameFilter
no value/proc^.*$oval:ssg-state_selinux_confinement_of_daemons:ste:1
Configure SELinux Policyxccdf_org.ssgproject.content_rule_selinux_policytype medium

Configure SELinux Policy

Rule IDxccdf_org.ssgproject.content_rule_selinux_policytype
Result
pass
Multi-check ruleno
OVAL Definition IDoval:ssg-selinux_policytype:def:1
Time2024-12-29T17:33:56+01:00
Severitymedium
Identifiers and References

References:  BP28(R66), 1, 11, 12, 13, 14, 15, 16, 18, 3, 4, 5, 6, 8, 9, APO01.06, APO11.04, APO13.01, BAI03.05, DSS01.05, DSS03.01, DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS06.02, DSS06.03, DSS06.06, MEA02.01, 3.1.2, 3.7.2, CCI-002165, CCI-002696, 164.308(a)(1)(ii)(D), 164.308(a)(3), 164.308(a)(4), 164.310(b), 164.310(c), 164.312(a), 164.312(e), 4.2.3.4, 4.3.3.2.2, 4.3.3.3.9, 4.3.3.4, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4, 4.4.3.3, SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.10, SR 2.11, SR 2.12, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 7.1, SR 7.6, A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.12.1.1, A.12.1.2, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.1.2, A.13.1.3, A.13.2.1, A.13.2.2, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.1, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5, CIP-003-8 R5.1.1, CIP-003-8 R5.2, CIP-003-8 R5.3, CIP-004-6 R2.2.3, CIP-004-6 R2.3, CIP-004-6 R3.3, CIP-007-3 R5.1, CIP-007-3 R5.1.2, CIP-007-3 R5.2, CIP-007-3 R5.3.1, CIP-007-3 R5.3.2, CIP-007-3 R5.3.3, CIP-007-3 R6.5, AC-3, AC-3(3)(a), AU-9, SC-7(21), DE.AE-1, ID.AM-3, PR.AC-4, PR.AC-5, PR.AC-6, PR.DS-5, PR.PT-1, PR.PT-3, PR.PT-4, SRG-OS-000445-GPOS-00199, SRG-OS-000445-VMM-001780

Description
The SELinux targeted policy is appropriate for general-purpose desktops and servers, as well as systems in many other roles. To configure the system to use this policy, add or correct the following line in /etc/selinux/config:
SELINUXTYPE=targeted
Other policies, such as mls, provide additional security labeling and greater confinement but are not compatible with many general-purpose use cases.
Rationale
Setting the SELinux policy to targeted or a more specialized policy ensures the system will confine processes that are likely to be targeted for exploitation, such as network or system services.

Note: During the development or debugging of SELinux modules, it is common to temporarily place non-production systems in permissive mode. In such temporary cases, SELinux policies should be developed, and once work is completed, the system should be reconfigured to targeted.
OVAL test results details

Tests the value of the ^[\s]*SELINUXTYPE[\s]*=[\s]*([^#]*) expression in the /etc/selinux/config file  oval:ssg-test_selinux_policy:tst:1  true

Following items have been found on the system:
PathContent
/etc/selinux/configSELINUXTYPE=targeted
Ensure SELinux State is Enforcingxccdf_org.ssgproject.content_rule_selinux_state medium

Ensure SELinux State is Enforcing

Rule IDxccdf_org.ssgproject.content_rule_selinux_state
Result
pass
Multi-check ruleno
OVAL Definition IDoval:ssg-selinux_state:def:1
Time2024-12-29T17:33:56+01:00
Severitymedium
Identifiers and References

References:  BP28(R4), BP28(R66), 1, 11, 12, 13, 14, 15, 16, 18, 3, 4, 5, 6, 8, 9, APO01.06, APO11.04, APO13.01, BAI03.05, DSS01.05, DSS03.01, DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS06.02, DSS06.03, DSS06.06, MEA02.01, 3.1.2, 3.7.2, CCI-002165, CCI-002696, 164.308(a)(1)(ii)(D), 164.308(a)(3), 164.308(a)(4), 164.310(b), 164.310(c), 164.312(a), 164.312(e), 4.2.3.4, 4.3.3.2.2, 4.3.3.3.9, 4.3.3.4, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4, 4.4.3.3, SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.10, SR 2.11, SR 2.12, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 7.1, SR 7.6, A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.12.1.1, A.12.1.2, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.1.2, A.13.1.3, A.13.2.1, A.13.2.2, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.1, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5, CIP-003-8 R5.1.1, CIP-003-8 R5.2, CIP-003-8 R5.3, CIP-004-6 R2.2.3, CIP-004-6 R2.3, CIP-004-6 R3.3, CIP-007-3 R5.1, CIP-007-3 R5.1.2, CIP-007-3 R5.2, CIP-007-3 R5.3.1, CIP-007-3 R5.3.2, CIP-007-3 R5.3.3, CIP-007-3 R6.5, AC-3, AC-3(3)(a), AU-9, SC-7(21), DE.AE-1, ID.AM-3, PR.AC-4, PR.AC-5, PR.AC-6, PR.DS-5, PR.PT-1, PR.PT-3, PR.PT-4, SRG-OS-000445-GPOS-00199, SRG-OS-000445-VMM-001780

Description
The SELinux state should be set to enforcing at system boot time. In the file /etc/selinux/config, add or correct the following line to configure the system to boot into enforcing mode:
SELINUX=enforcing
Rationale
Setting the SELinux state to enforcing ensures SELinux is able to confine potentially compromised processes to the security policy, which is designed to prevent them from causing damage to the system or further elevating their privileges.
OVAL test results details

/selinux/enforce is 1  oval:ssg-test_etc_selinux_config:tst:1  true

Following items have been found on the system:
PathContent
/etc/selinux/configSELINUX=enforcing
Uninstall Automatic Bug Reporting Tool (abrt)xccdf_org.ssgproject.content_rule_package_abrt_removed medium

Uninstall Automatic Bug Reporting Tool (abrt)

Rule IDxccdf_org.ssgproject.content_rule_package_abrt_removed
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-package_abrt_removed:def:1
Time2024-12-29T17:33:56+01:00
Severitymedium
Identifiers and References

References:  CCI-000381, SRG-OS-000095-GPOS-00049

Description
The Automatic Bug Reporting Tool (abrt) collects and reports crash data when an application crash is detected. Using a variety of plugins, abrt can email crash reports to system administrators, log crash reports to files, or forward crash reports to a centralized issue tracking system such as RHTSupport. The abrt package can be removed with the following command:
$ sudo dnf erase abrt
Rationale
Mishandling crash data could expose sensitive information about vulnerabilities in software executing on the system, as well as sensitive information from within a process's address space or registers.

Complexity:low
Disruption:low
Strategy:disable

# CAUTION: This remediation script will remove abrt
#	   from the system, and may remove any packages
#	   that depend on abrt. Execute this
#	   remediation AFTER testing on a non-production
#	   system!

if rpm -q --quiet "abrt" ; then

    dnf remove -y "abrt"

fi

Complexity:low
Disruption:low
Strategy:disable
- name: Ensure abrt is removed
  package:
    name: abrt
    state: absent
  tags:
    - disable_strategy
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - package_abrt_removed

Complexity:low
Disruption:low
Strategy:disable
include remove_abrt

class remove_abrt {
  package { 'abrt':
    ensure => 'purged',
  }
}

Complexity:low
Disruption:low
Strategy:disable

package --remove=abrt
OVAL test results details

package abrt is removed  oval:ssg-test_package_abrt_removed:tst:1  false

Following items have been found on the system:
NameArchEpochReleaseVersionEvrSignature keyidExtended name
abrtx86_64(none)4.fc342.14.60:2.14.6-4.fc341161ae6945719a39abrt-0:2.14.6-4.fc34.x86_64
Install fapolicyd Packagexccdf_org.ssgproject.content_rule_package_fapolicyd_installed medium

Install fapolicyd Package

Rule IDxccdf_org.ssgproject.content_rule_package_fapolicyd_installed
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-package_fapolicyd_installed:def:1
Time2024-12-29T17:33:56+01:00
Severitymedium
Identifiers and References

References:  CCI-001764, CM-6(a), SI-4(22), SRG-OS-000370-GPOS-00155, SRG-OS-000368-GPOS-00154

Description
The fapolicyd package can be installed with the following command:
$ sudo dnf install fapolicyd
Rationale
fapolicyd (File Access Policy Daemon) implements application whitelisting to decide file access rights.

Complexity:low
Disruption:low
Strategy:enable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

if ! rpm -q --quiet "fapolicyd" ; then
    dnf install -y "fapolicyd"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:enable
- name: Ensure fapolicyd is installed
  package:
    name: fapolicyd
    state: present
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-53-CM-6(a)
    - NIST-800-53-SI-4(22)
    - enable_strategy
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - package_fapolicyd_installed

Complexity:low
Disruption:low
Strategy:enable
include install_fapolicyd

class install_fapolicyd {
  package { 'fapolicyd':
    ensure => 'installed',
  }
}

Complexity:low
Disruption:low
Strategy:enable

package --add=fapolicyd


[[packages]]
name = "fapolicyd"
version = "*"
OVAL test results details

package fapolicyd is installed  oval:ssg-test_package_fapolicyd_installed:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_test_package_fapolicyd_installed:obj:1 of type rpminfo_object
Name
fapolicyd
Uninstall Sendmail Packagexccdf_org.ssgproject.content_rule_package_sendmail_removed medium

Uninstall Sendmail Package

Rule IDxccdf_org.ssgproject.content_rule_package_sendmail_removed
Result
pass
Multi-check ruleno
OVAL Definition IDoval:ssg-package_sendmail_removed:def:1
Time2024-12-29T17:33:56+01:00
Severitymedium
Identifiers and References

References:  BP28(R1), 11, 14, 3, 9, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS06.06, CCI-000381, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.3.2, 4.3.4.3.3, SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 7.6, A.12.1.2, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4, A.9.1.2, CM-7(a), CM-7(b), CM-6(a), PR.IP-1, PR.PT-3, SRG-OS-000480-GPOS-00227, SRG-OS-000095-GPOS-00049

Description
Sendmail is not the default mail transfer agent and is not installed by default. The sendmail package can be removed with the following command:
$ sudo dnf erase sendmail
Rationale
The sendmail software was not developed with security in mind and its design prevents it from being effectively contained by SELinux. Postfix should be used instead.
OVAL test results details

package sendmail is removed  oval:ssg-test_package_sendmail_removed:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-obj_test_package_sendmail_removed:obj:1 of type rpminfo_object
Name
sendmail
Disable chrony daemon from acting as serverxccdf_org.ssgproject.content_rule_chronyd_client_only low

Disable chrony daemon from acting as server

Rule IDxccdf_org.ssgproject.content_rule_chronyd_client_only
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-chronyd_client_only:def:1
Time2024-12-29T17:33:56+01:00
Severitylow
Identifiers and References

References:  CCI-000381, AU-8(1), FMT_SMF_EXT.1, SRG-OS-000096-GPOS-00050, SRG-OS-000095-GPOS-00049

Description
The port option in /etc/chrony.conf can be set to 0 to make chrony daemon to never open any listening port for server operation and to operate strictly in a client-only mode.
Rationale
Minimizing the exposure of the server functionality of the chrony daemon diminishes the attack surface.

# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

# Test if the config_file is a symbolic link. If so, use --follow-symlinks with sed.
# Otherwise, regular sed command will do.
sed_command=('sed' '-i')
if test -L "/etc/chrony.conf"; then
    sed_command+=('--follow-symlinks')
fi

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^port")

# shellcheck disable=SC2059
printf -v formatted_output "%s %s" "$stripped_key" "0"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^port\\>" "/etc/chrony.conf"; then
    "${sed_command[@]}" "s/^port\\>.*/$formatted_output/gi" "/etc/chrony.conf"
else
    # \n is precaution for case where file ends without trailing newline
    
    printf '%s\n' "$formatted_output" >> "/etc/chrony.conf"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,{{ %23%20Allow%20for%20extra%20configuration%20files.%20This%20is%20useful%0A%23%20for%20admins%20specifying%20their%20own%20NTP%20servers%0Ainclude%20/etc/chrony.d/%2A.conf%0A%0A%23%20Set%20chronyd%20as%20client-only.%0Aport%200%0A%0A%23%20Disable%20chronyc%20from%20the%20network%0Acmdport%200%0A%0A%23%20Record%20the%20rate%20at%20which%20the%20system%20clock%20gains/losses%20time.%0Adriftfile%20/var/lib/chrony/drift%0A%0A%23%20Allow%20the%20system%20clock%20to%20be%20stepped%20in%20the%20first%20three%20updates%0A%23%20if%20its%20offset%20is%20larger%20than%201%20second.%0Amakestep%201.0%203%0A%0A%23%20Enable%20kernel%20synchronization%20of%20the%20real-time%20clock%20%28RTC%29.%0Artcsync%0A%0A%23%20Enable%20hardware%20timestamping%20on%20all%20interfaces%20that%20support%20it.%0A%23hwtimestamp%20%2A%0A%0A%23%20Increase%20the%20minimum%20number%20of%20selectable%20sources%20required%20to%20adjust%0A%23%20the%20system%20clock.%0A%23minsources%202%0A%0A%23%20Allow%20NTP%20client%20access%20from%20local%20network.%0A%23allow%20192.168.0.0/16%0A%0A%23%20Serve%20time%20even%20if%20not%20synchronized%20to%20a%20time%20source.%0A%23local%20stratum%2010%0A%0A%23%20Require%20authentication%20%28nts%20or%20key%20option%29%20for%20all%20NTP%20sources.%0A%23authselectmode%20require%0A%0A%23%20Specify%20file%20containing%20keys%20for%20NTP%20authentication.%0Akeyfile%20/etc/chrony.keys%0A%0A%23%20Insert/delete%20leap%20seconds%20by%20slewing%20instead%20of%20stepping.%0A%23leapsecmode%20slew%0A%0A%23%20Get%20TAI-UTC%20offset%20and%20leap%20seconds%20from%20the%20system%20tz%20database.%0Aleapsectz%20right/UTC%0A%0A%23%20Specify%20directory%20for%20log%20files.%0Alogdir%20/var/log/chrony%0A%0A%23%20Select%20which%20information%20is%20logged.%0A%23log%20measurements%20statistics%20tracking }}
        mode: 420
        overwrite: true
        path: /etc/chrony.conf
      - contents:
          source: data:,
        mode: 420
        overwrite: true
        path: /etc/chrony.d/.mco-keep
      - contents:
          source: data:,{{ %23%0A%23%20This%20file%20controls%20the%20configuration%20of%20the%20ntp%20server%0A%23%20%7B%7B.var_multiple_time_servers%7D%7D%20we%20have%20to%20put%20variable%20array%20name%20here%20for%20mutilines%20remediation%20%0A%7B%7B%24var_time_service_set_maxpoll%3A%3D.var_time_service_set_maxpoll%7D%7D%0A%7B%7Brange%20%24element%3A%3D.var_multiple_time_servers%7CtoArrayByComma%7D%7Dserver%20%7B%7B%24element%7D%7D%20minpoll%204%20maxpoll%20%7B%7B%24var_time_service_set_maxpoll%7D%7D%0A%7B%7Bend%7D%7D }}
        mode: 420
        overwrite: true
        path: /etc/chrony.d/ntp-server.conf
OVAL test results details

package chrony is installed  oval:ssg-test_service_chronyd_package_chrony_installed:tst:1  true

Following items have been found on the system:
NameArchEpochReleaseVersionEvrSignature keyidExtended name
chronyx86_64(none)1.fc344.10:4.1-1.fc341161ae6945719a39chrony-0:4.1-1.fc34.x86_64

Test that the chronyd service is running  oval:ssg-test_service_running_chronyd:tst:1  true

Following items have been found on the system:
UnitPropertyValue
chronyd.serviceActiveStateactive

systemd test  oval:ssg-test_multi_user_wants_chronyd:tst:1  true

Following items have been found on the system:
UnitDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependency
multi-user.targetbasic.target-.mountsysinit.targetlvm2-lvmpolld.socketsystemd-update-utmp.servicesys-kernel-config.mountcryptsetup.targetsystemd-tmpfiles-setup-dev.servicesystemd-udevd.serviceveritysetup.targetsystemd-ask-password-console.pathsystemd-journal-catalog-update.serviceselinux-autorelabel-mark.servicesystemd-journald.serviceplymouth-start.servicelocal-fs.targetboot.mountsystemd-remount-fs.servicetmp.mountsystemd-repart.serviceswap.targetdev-zram0.swapsystemd-firstboot.servicedracut-shutdown.serviceplymouth-read-write.servicesystemd-udev-trigger.serviceimport-state.servicesystemd-sysctl.servicesystemd-sysusers.serviceproc-sys-fs-binfmt_misc.automountsystemd-journal-flush.servicemultipathd.servicelvm2-monitor.servicedev-hugepages.mountsystemd-update-done.servicesystemd-random-seed.servicedev-mqueue.mountsystemd-hwdb-update.serviceldconfig.servicesystemd-boot-system-token.servicesystemd-machine-id-commit.servicesystemd-tmpfiles-setup.servicesys-kernel-debug.mountiscsi-onboot.servicesys-fs-fuse-connections.mountsys-kernel-tracing.mountkmod-static-nodes.servicesystemd-modules-load.servicesystemd-binfmt.servicepaths.targetrpmdb-rebuild.servicetimers.targetfstrim.timersystemd-tmpfiles-clean.timerlogrotate.timerraid-check.timerdnf-makecache.timermlocate-updatedb.timerunbound-anchor.timerslices.targetsystem.slice-.slicesockets.targetcockpit.socketmultipathd.socketsystemd-udevd-control.socketdbus.socketsystemd-journald-dev-log.socketsssd-kcm.socketsystemd-initctl.socketpcscd.socketsystemd-userdbd.socketiscsid.socketsystemd-coredump.socketdm-event.socketsystemd-udevd-kernel.socketiscsiuio.socketsystemd-journald-audit.socketsystemd-journald.socketsssd.serviceatd.servicegetty.targetgetty@tty1.servicemcelog.serviceabrt-xorg.servicefirewalld.serviceabrt-oops.servicesystemd-resolved.servicesystemd-ask-password-wall.pathrsyslog.serviceabrtd.servicesshd.serviceabrt-journal-core.servicesystemd-update-utmp-runlevel.servicesystemd-oomd.serviceirqbalance.serviceModemManager.serviceplymouth-quit.servicesystemd-logind.servicesmartd.serviceauditd.servicechronyd.serviceremote-fs.targetiscsi.servicenfs-client.targetremote-fs-pre.targetauth-rpcgss-module.servicerpc-statd-notify.servicesystemd-homed.serviceplymouth-quit-wait.servicemdmonitor.serviceNetworkManager.serviceabrt-vmcore.servicesystemd-user-sessions.service

systemd test  oval:ssg-test_multi_user_wants_chronyd_socket:tst:1  false

Following items have been found on the system:
UnitDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependency
multi-user.targetbasic.target-.mountsysinit.targetlvm2-lvmpolld.socketsystemd-update-utmp.servicesys-kernel-config.mountcryptsetup.targetsystemd-tmpfiles-setup-dev.servicesystemd-udevd.serviceveritysetup.targetsystemd-ask-password-console.pathsystemd-journal-catalog-update.serviceselinux-autorelabel-mark.servicesystemd-journald.serviceplymouth-start.servicelocal-fs.targetboot.mountsystemd-remount-fs.servicetmp.mountsystemd-repart.serviceswap.targetdev-zram0.swapsystemd-firstboot.servicedracut-shutdown.serviceplymouth-read-write.servicesystemd-udev-trigger.serviceimport-state.servicesystemd-sysctl.servicesystemd-sysusers.serviceproc-sys-fs-binfmt_misc.automountsystemd-journal-flush.servicemultipathd.servicelvm2-monitor.servicedev-hugepages.mountsystemd-update-done.servicesystemd-random-seed.servicedev-mqueue.mountsystemd-hwdb-update.serviceldconfig.servicesystemd-boot-system-token.servicesystemd-machine-id-commit.servicesystemd-tmpfiles-setup.servicesys-kernel-debug.mountiscsi-onboot.servicesys-fs-fuse-connections.mountsys-kernel-tracing.mountkmod-static-nodes.servicesystemd-modules-load.servicesystemd-binfmt.servicepaths.targetrpmdb-rebuild.servicetimers.targetfstrim.timersystemd-tmpfiles-clean.timerlogrotate.timerraid-check.timerdnf-makecache.timermlocate-updatedb.timerunbound-anchor.timerslices.targetsystem.slice-.slicesockets.targetcockpit.socketmultipathd.socketsystemd-udevd-control.socketdbus.socketsystemd-journald-dev-log.socketsssd-kcm.socketsystemd-initctl.socketpcscd.socketsystemd-userdbd.socketiscsid.socketsystemd-coredump.socketdm-event.socketsystemd-udevd-kernel.socketiscsiuio.socketsystemd-journald-audit.socketsystemd-journald.socketsssd.serviceatd.servicegetty.targetgetty@tty1.servicemcelog.serviceabrt-xorg.servicefirewalld.serviceabrt-oops.servicesystemd-resolved.servicesystemd-ask-password-wall.pathrsyslog.serviceabrtd.servicesshd.serviceabrt-journal-core.servicesystemd-update-utmp-runlevel.servicesystemd-oomd.serviceirqbalance.serviceModemManager.serviceplymouth-quit.servicesystemd-logind.servicesmartd.serviceauditd.servicechronyd.serviceremote-fs.targetiscsi.servicenfs-client.targetremote-fs-pre.targetauth-rpcgss-module.servicerpc-statd-notify.servicesystemd-homed.serviceplymouth-quit-wait.servicemdmonitor.serviceNetworkManager.serviceabrt-vmcore.servicesystemd-user-sessions.service

check if port is 0 in /etc/chrony.conf  oval:ssg-test_chronyd_client_only:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_chronyd_port_value:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/chrony.conf^\s*port[\s]+(\S+)1
Disable network management of chrony daemonxccdf_org.ssgproject.content_rule_chronyd_no_chronyc_network low

Disable network management of chrony daemon

Rule IDxccdf_org.ssgproject.content_rule_chronyd_no_chronyc_network
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-chronyd_no_chronyc_network:def:1
Time2024-12-29T17:33:56+01:00
Severitylow
Identifiers and References

References:  CCI-000381, CM-7(1), FMT_SMF_EXT.1, SRG-OS-000096-GPOS-00050, SRG-OS-000095-GPOS-00049

Description
The cmdport option in /etc/chrony.conf can be set to 0 to stop chrony daemon from listening on the UDP port 323 for management connections made by chronyc.
Rationale
Not exposing the management interface of the chrony daemon on the network diminishes the attack space.

# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

# Test if the config_file is a symbolic link. If so, use --follow-symlinks with sed.
# Otherwise, regular sed command will do.
sed_command=('sed' '-i')
if test -L "/etc/chrony.conf"; then
    sed_command+=('--follow-symlinks')
fi

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^cmdport")

# shellcheck disable=SC2059
printf -v formatted_output "%s %s" "$stripped_key" "0"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^cmdport\\>" "/etc/chrony.conf"; then
    "${sed_command[@]}" "s/^cmdport\\>.*/$formatted_output/gi" "/etc/chrony.conf"
else
    # \n is precaution for case where file ends without trailing newline
    
    printf '%s\n' "$formatted_output" >> "/etc/chrony.conf"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,{{ %23%20Allow%20for%20extra%20configuration%20files.%20This%20is%20useful%0A%23%20for%20admins%20specifying%20their%20own%20NTP%20servers%0Ainclude%20/etc/chrony.d/%2A.conf%0A%0A%23%20Set%20chronyd%20as%20client-only.%0Aport%200%0A%0A%23%20Disable%20chronyc%20from%20the%20network%0Acmdport%200%0A%0A%23%20Record%20the%20rate%20at%20which%20the%20system%20clock%20gains/losses%20time.%0Adriftfile%20/var/lib/chrony/drift%0A%0A%23%20Allow%20the%20system%20clock%20to%20be%20stepped%20in%20the%20first%20three%20updates%0A%23%20if%20its%20offset%20is%20larger%20than%201%20second.%0Amakestep%201.0%203%0A%0A%23%20Enable%20kernel%20synchronization%20of%20the%20real-time%20clock%20%28RTC%29.%0Artcsync%0A%0A%23%20Enable%20hardware%20timestamping%20on%20all%20interfaces%20that%20support%20it.%0A%23hwtimestamp%20%2A%0A%0A%23%20Increase%20the%20minimum%20number%20of%20selectable%20sources%20required%20to%20adjust%0A%23%20the%20system%20clock.%0A%23minsources%202%0A%0A%23%20Allow%20NTP%20client%20access%20from%20local%20network.%0A%23allow%20192.168.0.0/16%0A%0A%23%20Serve%20time%20even%20if%20not%20synchronized%20to%20a%20time%20source.%0A%23local%20stratum%2010%0A%0A%23%20Require%20authentication%20%28nts%20or%20key%20option%29%20for%20all%20NTP%20sources.%0A%23authselectmode%20require%0A%0A%23%20Specify%20file%20containing%20keys%20for%20NTP%20authentication.%0Akeyfile%20/etc/chrony.keys%0A%0A%23%20Insert/delete%20leap%20seconds%20by%20slewing%20instead%20of%20stepping.%0A%23leapsecmode%20slew%0A%0A%23%20Get%20TAI-UTC%20offset%20and%20leap%20seconds%20from%20the%20system%20tz%20database.%0Aleapsectz%20right/UTC%0A%0A%23%20Specify%20directory%20for%20log%20files.%0Alogdir%20/var/log/chrony%0A%0A%23%20Select%20which%20information%20is%20logged.%0A%23log%20measurements%20statistics%20tracking }}
        mode: 420
        overwrite: true
        path: /etc/chrony.conf
      - contents:
          source: data:,
        mode: 420
        overwrite: true
        path: /etc/chrony.d/.mco-keep
      - contents:
          source: data:,{{ %23%0A%23%20This%20file%20controls%20the%20configuration%20of%20the%20ntp%20server%0A%23%20%7B%7B.var_multiple_time_servers%7D%7D%20we%20have%20to%20put%20variable%20array%20name%20here%20for%20mutilines%20remediation%20%0A%7B%7B%24var_time_service_set_maxpoll%3A%3D.var_time_service_set_maxpoll%7D%7D%0A%7B%7Brange%20%24element%3A%3D.var_multiple_time_servers%7CtoArrayByComma%7D%7Dserver%20%7B%7B%24element%7D%7D%20minpoll%204%20maxpoll%20%7B%7B%24var_time_service_set_maxpoll%7D%7D%0A%7B%7Bend%7D%7D }}
        mode: 420
        overwrite: true
        path: /etc/chrony.d/ntp-server.conf
OVAL test results details

package chrony is installed  oval:ssg-test_service_chronyd_package_chrony_installed:tst:1  true

Following items have been found on the system:
NameArchEpochReleaseVersionEvrSignature keyidExtended name
chronyx86_64(none)1.fc344.10:4.1-1.fc341161ae6945719a39chrony-0:4.1-1.fc34.x86_64

Test that the chronyd service is running  oval:ssg-test_service_running_chronyd:tst:1  true

Following items have been found on the system:
UnitPropertyValue
chronyd.serviceActiveStateactive

systemd test  oval:ssg-test_multi_user_wants_chronyd:tst:1  true

Following items have been found on the system:
UnitDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependency
multi-user.targetbasic.target-.mountsysinit.targetlvm2-lvmpolld.socketsystemd-update-utmp.servicesys-kernel-config.mountcryptsetup.targetsystemd-tmpfiles-setup-dev.servicesystemd-udevd.serviceveritysetup.targetsystemd-ask-password-console.pathsystemd-journal-catalog-update.serviceselinux-autorelabel-mark.servicesystemd-journald.serviceplymouth-start.servicelocal-fs.targetboot.mountsystemd-remount-fs.servicetmp.mountsystemd-repart.serviceswap.targetdev-zram0.swapsystemd-firstboot.servicedracut-shutdown.serviceplymouth-read-write.servicesystemd-udev-trigger.serviceimport-state.servicesystemd-sysctl.servicesystemd-sysusers.serviceproc-sys-fs-binfmt_misc.automountsystemd-journal-flush.servicemultipathd.servicelvm2-monitor.servicedev-hugepages.mountsystemd-update-done.servicesystemd-random-seed.servicedev-mqueue.mountsystemd-hwdb-update.serviceldconfig.servicesystemd-boot-system-token.servicesystemd-machine-id-commit.servicesystemd-tmpfiles-setup.servicesys-kernel-debug.mountiscsi-onboot.servicesys-fs-fuse-connections.mountsys-kernel-tracing.mountkmod-static-nodes.servicesystemd-modules-load.servicesystemd-binfmt.servicepaths.targetrpmdb-rebuild.servicetimers.targetfstrim.timersystemd-tmpfiles-clean.timerlogrotate.timerraid-check.timerdnf-makecache.timermlocate-updatedb.timerunbound-anchor.timerslices.targetsystem.slice-.slicesockets.targetcockpit.socketmultipathd.socketsystemd-udevd-control.socketdbus.socketsystemd-journald-dev-log.socketsssd-kcm.socketsystemd-initctl.socketpcscd.socketsystemd-userdbd.socketiscsid.socketsystemd-coredump.socketdm-event.socketsystemd-udevd-kernel.socketiscsiuio.socketsystemd-journald-audit.socketsystemd-journald.socketsssd.serviceatd.servicegetty.targetgetty@tty1.servicemcelog.serviceabrt-xorg.servicefirewalld.serviceabrt-oops.servicesystemd-resolved.servicesystemd-ask-password-wall.pathrsyslog.serviceabrtd.servicesshd.serviceabrt-journal-core.servicesystemd-update-utmp-runlevel.servicesystemd-oomd.serviceirqbalance.serviceModemManager.serviceplymouth-quit.servicesystemd-logind.servicesmartd.serviceauditd.servicechronyd.serviceremote-fs.targetiscsi.servicenfs-client.targetremote-fs-pre.targetauth-rpcgss-module.servicerpc-statd-notify.servicesystemd-homed.serviceplymouth-quit-wait.servicemdmonitor.serviceNetworkManager.serviceabrt-vmcore.servicesystemd-user-sessions.service

systemd test  oval:ssg-test_multi_user_wants_chronyd_socket:tst:1  false

Following items have been found on the system:
UnitDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependency
multi-user.targetbasic.target-.mountsysinit.targetlvm2-lvmpolld.socketsystemd-update-utmp.servicesys-kernel-config.mountcryptsetup.targetsystemd-tmpfiles-setup-dev.servicesystemd-udevd.serviceveritysetup.targetsystemd-ask-password-console.pathsystemd-journal-catalog-update.serviceselinux-autorelabel-mark.servicesystemd-journald.serviceplymouth-start.servicelocal-fs.targetboot.mountsystemd-remount-fs.servicetmp.mountsystemd-repart.serviceswap.targetdev-zram0.swapsystemd-firstboot.servicedracut-shutdown.serviceplymouth-read-write.servicesystemd-udev-trigger.serviceimport-state.servicesystemd-sysctl.servicesystemd-sysusers.serviceproc-sys-fs-binfmt_misc.automountsystemd-journal-flush.servicemultipathd.servicelvm2-monitor.servicedev-hugepages.mountsystemd-update-done.servicesystemd-random-seed.servicedev-mqueue.mountsystemd-hwdb-update.serviceldconfig.servicesystemd-boot-system-token.servicesystemd-machine-id-commit.servicesystemd-tmpfiles-setup.servicesys-kernel-debug.mountiscsi-onboot.servicesys-fs-fuse-connections.mountsys-kernel-tracing.mountkmod-static-nodes.servicesystemd-modules-load.servicesystemd-binfmt.servicepaths.targetrpmdb-rebuild.servicetimers.targetfstrim.timersystemd-tmpfiles-clean.timerlogrotate.timerraid-check.timerdnf-makecache.timermlocate-updatedb.timerunbound-anchor.timerslices.targetsystem.slice-.slicesockets.targetcockpit.socketmultipathd.socketsystemd-udevd-control.socketdbus.socketsystemd-journald-dev-log.socketsssd-kcm.socketsystemd-initctl.socketpcscd.socketsystemd-userdbd.socketiscsid.socketsystemd-coredump.socketdm-event.socketsystemd-udevd-kernel.socketiscsiuio.socketsystemd-journald-audit.socketsystemd-journald.socketsssd.serviceatd.servicegetty.targetgetty@tty1.servicemcelog.serviceabrt-xorg.servicefirewalld.serviceabrt-oops.servicesystemd-resolved.servicesystemd-ask-password-wall.pathrsyslog.serviceabrtd.servicesshd.serviceabrt-journal-core.servicesystemd-update-utmp-runlevel.servicesystemd-oomd.serviceirqbalance.serviceModemManager.serviceplymouth-quit.servicesystemd-logind.servicesmartd.serviceauditd.servicechronyd.serviceremote-fs.targetiscsi.servicenfs-client.targetremote-fs-pre.targetauth-rpcgss-module.servicerpc-statd-notify.servicesystemd-homed.serviceplymouth-quit-wait.servicemdmonitor.serviceNetworkManager.serviceabrt-vmcore.servicesystemd-user-sessions.service

check if cmdport is 0 in /etc/chrony.conf  oval:ssg-test_chronyd_no_chronyc_network:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_chronyd_cmdport_value:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/chrony.conf^\s*cmdport[\s]+(\S+)1
Enable the Hardware RNG Entropy Gatherer Servicexccdf_org.ssgproject.content_rule_service_rngd_enabled low

Enable the Hardware RNG Entropy Gatherer Service

Rule IDxccdf_org.ssgproject.content_rule_service_rngd_enabled
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-service_rngd_enabled:def:1
Time2024-12-29T17:33:56+01:00
Severitylow
Identifiers and References

References:  CCI-000366, FCS_RBG_EXT.1, SRG-OS-000480-GPOS-00227

Description
The Hardware RNG Entropy Gatherer service should be enabled. The rngd service can be enabled with the following command:
$ sudo systemctl enable rngd.service
Rationale
The rngd service feeds random data from hardware device to kernel random device.

Complexity:low
Disruption:low
Strategy:enable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

SYSTEMCTL_EXEC='/usr/bin/systemctl'
"$SYSTEMCTL_EXEC" unmask 'rngd.service'
"$SYSTEMCTL_EXEC" start 'rngd.service'
"$SYSTEMCTL_EXEC" enable 'rngd.service'

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:enable
- name: Enable service rngd
  block:

    - name: Gather the package facts
      package_facts:
        manager: auto

    - name: Enable service rngd
      service:
        name: rngd
        enabled: 'yes'
        state: started
        masked: 'no'
      when:
        - '"rng-tools" in ansible_facts.packages'
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - enable_strategy
    - low_complexity
    - low_disruption
    - low_severity
    - no_reboot_needed
    - service_rngd_enabled

Complexity:low
Disruption:low
Strategy:enable
include enable_rngd

class enable_rngd {
  service {'rngd':
    enable => true,
    ensure => 'running',
  }
}


[customizations.services]
enabled = ["rngd"]
OVAL test results details

package rng-tools is installed  oval:ssg-test_service_rngd_package_rng-tools_installed:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_test_service_rngd_package_rng-tools_installed:obj:1 of type rpminfo_object
Name
rng-tools

Test that the rngd service is running  oval:ssg-test_service_running_rngd:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_service_running_rngd:obj:1 of type systemdunitproperty_object
UnitProperty
^rngd\.(socket|service)$ActiveState

systemd test  oval:ssg-test_multi_user_wants_rngd:tst:1  false

Following items have been found on the system:
UnitDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependency
multi-user.targetbasic.target-.mountsysinit.targetlvm2-lvmpolld.socketsystemd-update-utmp.servicesys-kernel-config.mountcryptsetup.targetsystemd-tmpfiles-setup-dev.servicesystemd-udevd.serviceveritysetup.targetsystemd-ask-password-console.pathsystemd-journal-catalog-update.serviceselinux-autorelabel-mark.servicesystemd-journald.serviceplymouth-start.servicelocal-fs.targetboot.mountsystemd-remount-fs.servicetmp.mountsystemd-repart.serviceswap.targetdev-zram0.swapsystemd-firstboot.servicedracut-shutdown.serviceplymouth-read-write.servicesystemd-udev-trigger.serviceimport-state.servicesystemd-sysctl.servicesystemd-sysusers.serviceproc-sys-fs-binfmt_misc.automountsystemd-journal-flush.servicemultipathd.servicelvm2-monitor.servicedev-hugepages.mountsystemd-update-done.servicesystemd-random-seed.servicedev-mqueue.mountsystemd-hwdb-update.serviceldconfig.servicesystemd-boot-system-token.servicesystemd-machine-id-commit.servicesystemd-tmpfiles-setup.servicesys-kernel-debug.mountiscsi-onboot.servicesys-fs-fuse-connections.mountsys-kernel-tracing.mountkmod-static-nodes.servicesystemd-modules-load.servicesystemd-binfmt.servicepaths.targetrpmdb-rebuild.servicetimers.targetfstrim.timersystemd-tmpfiles-clean.timerlogrotate.timerraid-check.timerdnf-makecache.timermlocate-updatedb.timerunbound-anchor.timerslices.targetsystem.slice-.slicesockets.targetcockpit.socketmultipathd.socketsystemd-udevd-control.socketdbus.socketsystemd-journald-dev-log.socketsssd-kcm.socketsystemd-initctl.socketpcscd.socketsystemd-userdbd.socketiscsid.socketsystemd-coredump.socketdm-event.socketsystemd-udevd-kernel.socketiscsiuio.socketsystemd-journald-audit.socketsystemd-journald.socketsssd.serviceatd.servicegetty.targetgetty@tty1.servicemcelog.serviceabrt-xorg.servicefirewalld.serviceabrt-oops.servicesystemd-resolved.servicesystemd-ask-password-wall.pathrsyslog.serviceabrtd.servicesshd.serviceabrt-journal-core.servicesystemd-update-utmp-runlevel.servicesystemd-oomd.serviceirqbalance.serviceModemManager.serviceplymouth-quit.servicesystemd-logind.servicesmartd.serviceauditd.servicechronyd.serviceremote-fs.targetiscsi.servicenfs-client.targetremote-fs-pre.targetauth-rpcgss-module.servicerpc-statd-notify.servicesystemd-homed.serviceplymouth-quit-wait.servicemdmonitor.serviceNetworkManager.serviceabrt-vmcore.servicesystemd-user-sessions.service

systemd test  oval:ssg-test_multi_user_wants_rngd_socket:tst:1  false

Following items have been found on the system:
UnitDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependencyDependency
multi-user.targetbasic.target-.mountsysinit.targetlvm2-lvmpolld.socketsystemd-update-utmp.servicesys-kernel-config.mountcryptsetup.targetsystemd-tmpfiles-setup-dev.servicesystemd-udevd.serviceveritysetup.targetsystemd-ask-password-console.pathsystemd-journal-catalog-update.serviceselinux-autorelabel-mark.servicesystemd-journald.serviceplymouth-start.servicelocal-fs.targetboot.mountsystemd-remount-fs.servicetmp.mountsystemd-repart.serviceswap.targetdev-zram0.swapsystemd-firstboot.servicedracut-shutdown.serviceplymouth-read-write.servicesystemd-udev-trigger.serviceimport-state.servicesystemd-sysctl.servicesystemd-sysusers.serviceproc-sys-fs-binfmt_misc.automountsystemd-journal-flush.servicemultipathd.servicelvm2-monitor.servicedev-hugepages.mountsystemd-update-done.servicesystemd-random-seed.servicedev-mqueue.mountsystemd-hwdb-update.serviceldconfig.servicesystemd-boot-system-token.servicesystemd-machine-id-commit.servicesystemd-tmpfiles-setup.servicesys-kernel-debug.mountiscsi-onboot.servicesys-fs-fuse-connections.mountsys-kernel-tracing.mountkmod-static-nodes.servicesystemd-modules-load.servicesystemd-binfmt.servicepaths.targetrpmdb-rebuild.servicetimers.targetfstrim.timersystemd-tmpfiles-clean.timerlogrotate.timerraid-check.timerdnf-makecache.timermlocate-updatedb.timerunbound-anchor.timerslices.targetsystem.slice-.slicesockets.targetcockpit.socketmultipathd.socketsystemd-udevd-control.socketdbus.socketsystemd-journald-dev-log.socketsssd-kcm.socketsystemd-initctl.socketpcscd.socketsystemd-userdbd.socketiscsid.socketsystemd-coredump.socketdm-event.socketsystemd-udevd-kernel.socketiscsiuio.socketsystemd-journald-audit.socketsystemd-journald.socketsssd.serviceatd.servicegetty.targetgetty@tty1.servicemcelog.serviceabrt-xorg.servicefirewalld.serviceabrt-oops.servicesystemd-resolved.servicesystemd-ask-password-wall.pathrsyslog.serviceabrtd.servicesshd.serviceabrt-journal-core.servicesystemd-update-utmp-runlevel.servicesystemd-oomd.serviceirqbalance.serviceModemManager.serviceplymouth-quit.servicesystemd-logind.servicesmartd.serviceauditd.servicechronyd.serviceremote-fs.targetiscsi.servicenfs-client.targetremote-fs-pre.targetauth-rpcgss-module.servicerpc-statd-notify.servicesystemd-homed.serviceplymouth-quit-wait.servicemdmonitor.serviceNetworkManager.serviceabrt-vmcore.servicesystemd-user-sessions.service
Disable Host-Based Authenticationxccdf_org.ssgproject.content_rule_disable_host_auth medium

Disable Host-Based Authentication

Rule IDxccdf_org.ssgproject.content_rule_disable_host_auth
Result
pass
Multi-check ruleno
OVAL Definition IDoval:ssg-disable_host_auth:def:1
Time2024-12-29T17:33:56+01:00
Severitymedium
Identifiers and References

References:  11, 12, 14, 15, 16, 18, 3, 5, 9, 5.5.6, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS06.03, DSS06.06, 3.1.12, CCI-000366, 164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii), 4.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.3.2, 4.3.4.3.3, SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 7.6, 0421, 0422, 0431, 0974, 1173, 1401, 1504, 1505, 1546, 1557, 1558, 1559, 1560, 1561, A.12.1.2, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4, A.6.1.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5, CIP-003-8 R5.1.1, CIP-003-8 R5.3, CIP-004-6 R2.2.3, CIP-004-6 R2.3, CIP-007-3 R5.1, CIP-007-3 R5.1.2, CIP-007-3 R5.2, CIP-007-3 R5.3.1, CIP-007-3 R5.3.2, CIP-007-3 R5.3.3, AC-3, AC-17(a), CM-7(a), CM-7(b), CM-6(a), PR.AC-4, PR.AC-6, PR.IP-1, PR.PT-3, FIA_UAU.1, SRG-OS-000480-GPOS-00229, SRG-OS-000480-VMM-002000

Description
SSH's cryptographic host-based authentication is more secure than .rhosts authentication. However, it is not recommended that hosts unilaterally trust one another, even within an organization.
The default SSH configuration disables host-based authentication. The appropriate configuration is used if no value is set for HostbasedAuthentication.
To explicitly disable host-based authentication, add or correct the following line in /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf:
HostbasedAuthentication no
Rationale
SSH trust relationships mean a compromise on one host can allow an attacker to move trivially to other hosts.
OVAL test results details

Verify if Profile set Value sshd_required as not required  oval:ssg-test_sshd_not_required:tst:1  false

Following items have been found on the system:
Var refValue
oval:ssg-sshd_required:var:10

Verify if Value of sshd_required is the default  oval:ssg-test_sshd_requirement_unset:tst:1  true

Following items have been found on the system:
Var refValue
oval:ssg-sshd_required:var:10

package openssh-server is removed  oval:ssg-test_package_openssh-server_removed:tst:1  false

Following items have been found on the system:
NameArchEpochReleaseVersionEvrSignature keyidExtended name
openssh-serverx86_64(none)5.fc348.6p10:8.6p1-5.fc341161ae6945719a39openssh-server-0:8.6p1-5.fc34.x86_64

Verify if Profile set Value sshd_required as required  oval:ssg-test_sshd_required:tst:1  false

Following items have been found on the system:
Var refValue
oval:ssg-sshd_required:var:10

Verify if Value of sshd_required is the default  oval:ssg-test_sshd_requirement_unset:tst:1  true

Following items have been found on the system:
Var refValue
oval:ssg-sshd_required:var:10

package openssh-server is installed  oval:ssg-test_package_openssh-server_installed:tst:1  true

Following items have been found on the system:
NameArchEpochReleaseVersionEvrSignature keyidExtended name
openssh-serverx86_64(none)5.fc348.6p10:8.6p1-5.fc341161ae6945719a39openssh-server-0:8.6p1-5.fc34.x86_64

tests the value of HostbasedAuthentication setting in the /etc/ssh/sshd_config file  oval:ssg-test_disable_host_auth:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_disable_host_auth:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/ssh/sshd_config^[ \t]*(?i)HostbasedAuthentication(?-i)[ \t]+(.+?)[ \t]*(?:$|#)1

tests the absence of HostbasedAuthentication setting in the /etc/ssh/sshd_config file  oval:ssg-test_disable_host_auth_default_not_overriden:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-obj_disable_host_auth_default_not_overriden:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/ssh/sshd_config^[ \t]*(?i)HostbasedAuthentication(?-i)[ \t]+1

tests the absence of HostbasedAuthentication setting in the /etc/ssh/sshd_config.d file  oval:ssg-test_disable_host_auth_config_dir_default_not_overriden:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-obj_disable_host_auth_config_dir_default_not_overriden:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/etc/ssh/sshd_config.d.*\.conf$^[ \t]*(?i)HostbasedAuthentication(?-i)[ \t]+1

tests the value of HostbasedAuthentication setting in the /etc/ssh/sshd_config.d file  oval:ssg-test_disable_host_auth_config_dir:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_disable_host_auth_config_dir:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/etc/ssh/sshd_config.d.*\.conf$^[ \t]*(?i)HostbasedAuthentication(?-i)[ \t]+(.+?)[ \t]*(?:$|#)1
Disable SSH Access via Empty Passwordsxccdf_org.ssgproject.content_rule_sshd_disable_empty_passwords high

Disable SSH Access via Empty Passwords

Rule IDxccdf_org.ssgproject.content_rule_sshd_disable_empty_passwords
Result
pass
Multi-check ruleno
OVAL Definition IDoval:ssg-sshd_disable_empty_passwords:def:1
Time2024-12-29T17:33:56+01:00
Severityhigh
Identifiers and References

References:  NT007(R17), 11, 12, 13, 14, 15, 16, 18, 3, 5, 9, 5.5.6, APO01.06, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS06.02, DSS06.03, DSS06.06, 3.1.1, 3.1.5, CCI-000366, CCI-000766, 164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii), 4.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.3.2, 4.3.4.3.3, SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 5.2, SR 7.6, A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.12.1.2, A.12.5.1, A.12.6.2, A.13.1.1, A.13.1.3, A.13.2.1, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.1, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5, AC-17(a), CM-7(a), CM-7(b), CM-6(a), PR.AC-4, PR.AC-6, PR.DS-5, PR.IP-1, PR.PT-3, FIA_UAU.1, SRG-OS-000106-GPOS-00053, SRG-OS-000480-GPOS-00229, SRG-OS-000480-GPOS-00227, SRG-OS-000480-VMM-002000

Description
Disallow SSH login with empty passwords. The default SSH configuration disables logins with empty passwords. The appropriate configuration is used if no value is set for PermitEmptyPasswords.
To explicitly disallow SSH login from accounts with empty passwords, add or correct the following line in /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf:
PermitEmptyPasswords no
Any accounts with empty passwords should be disabled immediately, and PAM configuration should prevent users from being able to assign themselves empty passwords.
Rationale
Configuring this setting for the SSH daemon provides additional assurance that remote login via SSH will require a password, even in the event of misconfiguration elsewhere.
OVAL test results details

Verify if Profile set Value sshd_required as not required  oval:ssg-test_sshd_not_required:tst:1  false

Following items have been found on the system:
Var refValue
oval:ssg-sshd_required:var:10

Verify if Value of sshd_required is the default  oval:ssg-test_sshd_requirement_unset:tst:1  true

Following items have been found on the system:
Var refValue
oval:ssg-sshd_required:var:10

package openssh-server is removed  oval:ssg-test_package_openssh-server_removed:tst:1  false

Following items have been found on the system:
NameArchEpochReleaseVersionEvrSignature keyidExtended name
openssh-serverx86_64(none)5.fc348.6p10:8.6p1-5.fc341161ae6945719a39openssh-server-0:8.6p1-5.fc34.x86_64

Verify if Profile set Value sshd_required as required  oval:ssg-test_sshd_required:tst:1  false

Following items have been found on the system:
Var refValue
oval:ssg-sshd_required:var:10

Verify if Value of sshd_required is the default  oval:ssg-test_sshd_requirement_unset:tst:1  true

Following items have been found on the system:
Var refValue
oval:ssg-sshd_required:var:10

package openssh-server is installed  oval:ssg-test_package_openssh-server_installed:tst:1  true

Following items have been found on the system:
NameArchEpochReleaseVersionEvrSignature keyidExtended name
openssh-serverx86_64(none)5.fc348.6p10:8.6p1-5.fc341161ae6945719a39openssh-server-0:8.6p1-5.fc34.x86_64

tests the value of PermitEmptyPasswords setting in the /etc/ssh/sshd_config file  oval:ssg-test_sshd_disable_empty_passwords:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_sshd_disable_empty_passwords:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/ssh/sshd_config^[ \t]*(?i)PermitEmptyPasswords(?-i)[ \t]+(.+?)[ \t]*(?:$|#)1

tests the absence of PermitEmptyPasswords setting in the /etc/ssh/sshd_config file  oval:ssg-test_sshd_disable_empty_passwords_default_not_overriden:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-obj_sshd_disable_empty_passwords_default_not_overriden:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/ssh/sshd_config^[ \t]*(?i)PermitEmptyPasswords(?-i)[ \t]+1

tests the absence of PermitEmptyPasswords setting in the /etc/ssh/sshd_config.d file  oval:ssg-test_sshd_disable_empty_passwords_config_dir_default_not_overriden:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-obj_sshd_disable_empty_passwords_config_dir_default_not_overriden:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/etc/ssh/sshd_config.d.*\.conf$^[ \t]*(?i)PermitEmptyPasswords(?-i)[ \t]+1

tests the value of PermitEmptyPasswords setting in the /etc/ssh/sshd_config.d file  oval:ssg-test_sshd_disable_empty_passwords_config_dir:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_sshd_disable_empty_passwords_config_dir:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/etc/ssh/sshd_config.d.*\.conf$^[ \t]*(?i)PermitEmptyPasswords(?-i)[ \t]+(.+?)[ \t]*(?:$|#)1
Disable GSSAPI Authenticationxccdf_org.ssgproject.content_rule_sshd_disable_gssapi_auth medium

Disable GSSAPI Authentication

Rule IDxccdf_org.ssgproject.content_rule_sshd_disable_gssapi_auth
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-sshd_disable_gssapi_auth:def:1
Time2024-12-29T17:33:56+01:00
Severitymedium
Identifiers and References

References:  11, 3, 9, BAI10.01, BAI10.02, BAI10.03, BAI10.05, 3.1.12, CCI-000318, CCI-000368, CCI-001812, CCI-001813, CCI-001814, CCI-000366, 164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii), 4.3.4.3.2, 4.3.4.3.3, SR 7.6, 0418, 1055, 1402, A.12.1.2, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4, CM-7(a), CM-7(b), CM-6(a), AC-17(a), PR.IP-1, FTP_ITC_EXT.1, SRG-OS-000364-GPOS-00151, SRG-OS-000480-GPOS-00227, SRG-OS-000480-VMM-002000

Description
Unless needed, SSH should not permit extraneous or unnecessary authentication mechanisms like GSSAPI.
The default SSH configuration disallows authentications based on GSSAPI. The appropriate configuration is used if no value is set for GSSAPIAuthentication.
To explicitly disable GSSAPI authentication, add or correct the following line in /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf:
GSSAPIAuthentication no
Rationale
GSSAPI authentication is used to provide additional authentication mechanisms to applications. Allowing GSSAPI authentication through SSH exposes the system's GSSAPI to remote hosts, increasing the attack surface of the system.

Complexity:low
Disruption:low
Strategy:restrict
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

mkdir -p /etc/ssh/sshd_config.d
touch /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf

LC_ALL=C sed -i "/^\s*GSSAPIAuthentication\s\+/Id" "/etc/ssh/sshd_config"
LC_ALL=C sed -i "/^\s*GSSAPIAuthentication\s\+/Id" "/etc/ssh/sshd_config.d"/*.conf
if [ -e "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf" ] ; then
    
    LC_ALL=C sed -i "/^\s*GSSAPIAuthentication\s\+/Id" "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
else
    touch "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"

cp "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf" "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak"
# Insert before the line matching the regex '^Match'.
line_number="$(LC_ALL=C grep -n "^Match" "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak" | LC_ALL=C sed 's/:.*//g')"
if [ -z "$line_number" ]; then
    # There was no match of '^Match', insert at
    # the end of the file.
    printf '%s\n' "GSSAPIAuthentication no" >> "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
else
    head -n "$(( line_number - 1 ))" "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak" > "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
    printf '%s\n' "GSSAPIAuthentication no" >> "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
    tail -n "+$(( line_number ))" "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak" >> "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
fi
# Clean up after ourselves.
rm "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak"

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Disable GSSAPI Authentication
  block:

    - name: Deduplicate values from /etc/ssh/sshd_config
      lineinfile:
        path: /etc/ssh/sshd_config
        create: false
        regexp: ^\s*{{ "GSSAPIAuthentication"| regex_escape }}\s+
        state: absent

    - name: Check if /etc/ssh/sshd_config.d exists
      stat:
        path: /etc/ssh/sshd_config.d
      register: _etc_ssh_sshd_config_d_exists

    - name: Check if the parameter GSSAPIAuthentication is present in /etc/ssh/sshd_config.d
      find:
        paths: /etc/ssh/sshd_config.d
        recurse: 'yes'
        follow: 'no'
        contains: ^\s*{{ "GSSAPIAuthentication"| regex_escape }}\s+
      register: _etc_ssh_sshd_config_d_has_parameter
      when: _etc_ssh_sshd_config_d_exists.stat.isdir is defined and _etc_ssh_sshd_config_d_exists.stat.isdir

    - name: Remove parameter from files in /etc/ssh/sshd_config.d
      lineinfile:
        path: '{{ item.path }}'
        create: false
        regexp: ^\s*{{ "GSSAPIAuthentication"| regex_escape }}\s+
        state: absent
      with_items: '{{ _etc_ssh_sshd_config_d_has_parameter.files }}'
      when: _etc_ssh_sshd_config_d_has_parameter.matched

    - name: Insert correct line to /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf
      lineinfile:
        path: /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf
        create: true
        regexp: ^\s*{{ "GSSAPIAuthentication"| regex_escape }}\s+
        line: GSSAPIAuthentication no
        state: present
        insertbefore: ^[#\s]*Match
        validate: /usr/sbin/sshd -t -f %s
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - NIST-800-171-3.1.12
    - NIST-800-53-AC-17(a)
    - NIST-800-53-CM-6(a)
    - NIST-800-53-CM-7(a)
    - NIST-800-53-CM-7(b)
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
    - sshd_disable_gssapi_auth
OVAL test results details

Verify if Profile set Value sshd_required as not required  oval:ssg-test_sshd_not_required:tst:1  false

Following items have been found on the system:
Var refValue
oval:ssg-sshd_required:var:10

Verify if Value of sshd_required is the default  oval:ssg-test_sshd_requirement_unset:tst:1  true

Following items have been found on the system:
Var refValue
oval:ssg-sshd_required:var:10

package openssh-server is removed  oval:ssg-test_package_openssh-server_removed:tst:1  false

Following items have been found on the system:
NameArchEpochReleaseVersionEvrSignature keyidExtended name
openssh-serverx86_64(none)5.fc348.6p10:8.6p1-5.fc341161ae6945719a39openssh-server-0:8.6p1-5.fc34.x86_64

Verify if Profile set Value sshd_required as required  oval:ssg-test_sshd_required:tst:1  false

Following items have been found on the system:
Var refValue
oval:ssg-sshd_required:var:10

Verify if Value of sshd_required is the default  oval:ssg-test_sshd_requirement_unset:tst:1  true

Following items have been found on the system:
Var refValue
oval:ssg-sshd_required:var:10

package openssh-server is installed  oval:ssg-test_package_openssh-server_installed:tst:1  true

Following items have been found on the system:
NameArchEpochReleaseVersionEvrSignature keyidExtended name
openssh-serverx86_64(none)5.fc348.6p10:8.6p1-5.fc341161ae6945719a39openssh-server-0:8.6p1-5.fc34.x86_64

tests the value of GSSAPIAuthentication setting in the /etc/ssh/sshd_config file  oval:ssg-test_sshd_disable_gssapi_auth:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_sshd_disable_gssapi_auth:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/ssh/sshd_config^[ \t]*(?i)GSSAPIAuthentication(?-i)[ \t]+(.+?)[ \t]*(?:$|#)1

tests the absence of GSSAPIAuthentication setting in the /etc/ssh/sshd_config file  oval:ssg-test_sshd_disable_gssapi_auth_default_not_overriden:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-obj_sshd_disable_gssapi_auth_default_not_overriden:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/ssh/sshd_config^[ \t]*(?i)GSSAPIAuthentication(?-i)[ \t]+1

tests the absence of GSSAPIAuthentication setting in the /etc/ssh/sshd_config.d file  oval:ssg-test_sshd_disable_gssapi_auth_config_dir_default_not_overriden:tst:1  false

Following items have been found on the system:
PathContent
/etc/ssh/sshd_config.d/50-redhat.confGSSAPIAuthentication

tests the value of GSSAPIAuthentication setting in the /etc/ssh/sshd_config.d file  oval:ssg-test_sshd_disable_gssapi_auth_config_dir:tst:1  false

Following items have been found on the system:
PathContent
/etc/ssh/sshd_config.d/50-redhat.confGSSAPIAuthentication yes
Disable Kerberos Authenticationxccdf_org.ssgproject.content_rule_sshd_disable_kerb_auth medium

Disable Kerberos Authentication

Rule IDxccdf_org.ssgproject.content_rule_sshd_disable_kerb_auth
Result
pass
Multi-check ruleno
OVAL Definition IDoval:ssg-sshd_disable_kerb_auth:def:1
Time2024-12-29T17:33:56+01:00
Severitymedium
Identifiers and References

References:  11, 3, 9, BAI10.01, BAI10.02, BAI10.03, BAI10.05, 3.1.12, CCI-000318, CCI-000368, CCI-001812, CCI-001813, CCI-001814, CCI-000366, 164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii), 4.3.4.3.2, 4.3.4.3.3, SR 7.6, 0421, 0422, 0431, 0974, 1173, 1401, 1504, 1505, 1546, 1557, 1558, 1559, 1560, 1561, A.12.1.2, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4, AC-17(a), CM-7(a), CM-7(b), CM-6(a), PR.IP-1, FTP_ITC_EXT.1, SRG-OS-000364-GPOS-00151, SRG-OS-000480-GPOS-00227, SRG-OS-000480-VMM-002000

Description
Unless needed, SSH should not permit extraneous or unnecessary authentication mechanisms like Kerberos.
The default SSH configuration disallows authentication validation through Kerberos. The appropriate configuration is used if no value is set for KerberosAuthentication.
To explicitly disable Kerberos authentication, add or correct the following line in /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf:
KerberosAuthentication no
Rationale
Kerberos authentication for SSH is often implemented using GSSAPI. If Kerberos is enabled through SSH, the SSH daemon provides a means of access to the system's Kerberos implementation. Vulnerabilities in the system's Kerberos implementations may be subject to exploitation.
OVAL test results details

Verify if Profile set Value sshd_required as not required  oval:ssg-test_sshd_not_required:tst:1  false

Following items have been found on the system:
Var refValue
oval:ssg-sshd_required:var:10

Verify if Value of sshd_required is the default  oval:ssg-test_sshd_requirement_unset:tst:1  true

Following items have been found on the system:
Var refValue
oval:ssg-sshd_required:var:10

package openssh-server is removed  oval:ssg-test_package_openssh-server_removed:tst:1  false

Following items have been found on the system:
NameArchEpochReleaseVersionEvrSignature keyidExtended name
openssh-serverx86_64(none)5.fc348.6p10:8.6p1-5.fc341161ae6945719a39openssh-server-0:8.6p1-5.fc34.x86_64

Verify if Profile set Value sshd_required as required  oval:ssg-test_sshd_required:tst:1  false

Following items have been found on the system:
Var refValue
oval:ssg-sshd_required:var:10

Verify if Value of sshd_required is the default  oval:ssg-test_sshd_requirement_unset:tst:1  true

Following items have been found on the system:
Var refValue
oval:ssg-sshd_required:var:10

package openssh-server is installed  oval:ssg-test_package_openssh-server_installed:tst:1  true

Following items have been found on the system:
NameArchEpochReleaseVersionEvrSignature keyidExtended name
openssh-serverx86_64(none)5.fc348.6p10:8.6p1-5.fc341161ae6945719a39openssh-server-0:8.6p1-5.fc34.x86_64

tests the value of KerberosAuthentication setting in the /etc/ssh/sshd_config file  oval:ssg-test_sshd_disable_kerb_auth:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_sshd_disable_kerb_auth:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/ssh/sshd_config^[ \t]*(?i)KerberosAuthentication(?-i)[ \t]+(.+?)[ \t]*(?:$|#)1

tests the absence of KerberosAuthentication setting in the /etc/ssh/sshd_config file  oval:ssg-test_sshd_disable_kerb_auth_default_not_overriden:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-obj_sshd_disable_kerb_auth_default_not_overriden:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/ssh/sshd_config^[ \t]*(?i)KerberosAuthentication(?-i)[ \t]+1

tests the absence of KerberosAuthentication setting in the /etc/ssh/sshd_config.d file  oval:ssg-test_sshd_disable_kerb_auth_config_dir_default_not_overriden:tst:1  true

No items have been found conforming to the following objects:
Object oval:ssg-obj_sshd_disable_kerb_auth_config_dir_default_not_overriden:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/etc/ssh/sshd_config.d.*\.conf$^[ \t]*(?i)KerberosAuthentication(?-i)[ \t]+1

tests the value of KerberosAuthentication setting in the /etc/ssh/sshd_config.d file  oval:ssg-test_sshd_disable_kerb_auth_config_dir:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_sshd_disable_kerb_auth_config_dir:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/etc/ssh/sshd_config.d.*\.conf$^[ \t]*(?i)KerberosAuthentication(?-i)[ \t]+(.+?)[ \t]*(?:$|#)1
Enable SSH Warning Bannerxccdf_org.ssgproject.content_rule_sshd_enable_warning_banner medium

Enable SSH Warning Banner

Rule IDxccdf_org.ssgproject.content_rule_sshd_enable_warning_banner
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-sshd_enable_warning_banner:def:1
Time2024-12-29T17:33:56+01:00
Severitymedium
Identifiers and References

References:  1, 12, 15, 16, 5.5.6, DSS05.04, DSS05.10, DSS06.10, 3.1.9, CCI-000048, CCI-000050, CCI-001384, CCI-001385, CCI-001386, CCI-001387, CCI-001388, 164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii), 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, SR 1.1, SR 1.10, SR 1.2, SR 1.5, SR 1.7, SR 1.8, SR 1.9, A.18.1.4, A.9.2.1, A.9.2.4, A.9.3.1, A.9.4.2, A.9.4.3, AC-8(a), AC-8(c), AC-17(a), CM-6(a), PR.AC-7, FTA_TAB.1, SRG-OS-000023-GPOS-00006, SRG-OS-000024-GPOS-00007, SRG-OS-000228-GPOS-00088, SRG-OS-000023-VMM-000060, SRG-OS-000024-VMM-000070

Description
To enable the warning banner and ensure it is consistent across the system, add or correct the following line in /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf:
Banner /etc/issue
Another section contains information on how to create an appropriate system-wide warning banner.
Rationale
The warning message reinforces policy awareness during the logon process and facilitates possible legal action against attackers. Alternatively, systems whose ownership should not be obvious should ensure usage of a banner that does not provide easy attribution.

Complexity:low
Disruption:low
Strategy:restrict
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

mkdir -p /etc/ssh/sshd_config.d
touch /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf

LC_ALL=C sed -i "/^\s*Banner\s\+/Id" "/etc/ssh/sshd_config"
LC_ALL=C sed -i "/^\s*Banner\s\+/Id" "/etc/ssh/sshd_config.d"/*.conf
if [ -e "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf" ] ; then
    
    LC_ALL=C sed -i "/^\s*Banner\s\+/Id" "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
else
    touch "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"

cp "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf" "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak"
# Insert before the line matching the regex '^Match'.
line_number="$(LC_ALL=C grep -n "^Match" "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak" | LC_ALL=C sed 's/:.*//g')"
if [ -z "$line_number" ]; then
    # There was no match of '^Match', insert at
    # the end of the file.
    printf '%s\n' "Banner /etc/issue" >> "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
else
    head -n "$(( line_number - 1 ))" "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak" > "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
    printf '%s\n' "Banner /etc/issue" >> "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
    tail -n "+$(( line_number ))" "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak" >> "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
fi
# Clean up after ourselves.
rm "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak"

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:restrict
- name: Enable SSH Warning Banner
  block:

    - name: Deduplicate values from /etc/ssh/sshd_config
      lineinfile:
        path: /etc/ssh/sshd_config
        create: false
        regexp: ^\s*{{ "Banner"| regex_escape }}\s+
        state: absent

    - name: Check if /etc/ssh/sshd_config.d exists
      stat:
        path: /etc/ssh/sshd_config.d
      register: _etc_ssh_sshd_config_d_exists

    - name: Check if the parameter Banner is present in /etc/ssh/sshd_config.d
      find:
        paths: /etc/ssh/sshd_config.d
        recurse: 'yes'
        follow: 'no'
        contains: ^\s*{{ "Banner"| regex_escape }}\s+
      register: _etc_ssh_sshd_config_d_has_parameter
      when: _etc_ssh_sshd_config_d_exists.stat.isdir is defined and _etc_ssh_sshd_config_d_exists.stat.isdir

    - name: Remove parameter from files in /etc/ssh/sshd_config.d
      lineinfile:
        path: '{{ item.path }}'
        create: false
        regexp: ^\s*{{ "Banner"| regex_escape }}\s+
        state: absent
      with_items: '{{ _etc_ssh_sshd_config_d_has_parameter.files }}'
      when: _etc_ssh_sshd_config_d_has_parameter.matched

    - name: Insert correct line to /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf
      lineinfile:
        path: /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf
        create: true
        regexp: ^\s*{{ "Banner"| regex_escape }}\s+
        line: Banner /etc/issue
        state: present
        insertbefore: ^[#\s]*Match
        validate: /usr/sbin/sshd -t -f %s
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - CJIS-5.5.6
    - NIST-800-171-3.1.9
    - NIST-800-53-AC-17(a)
    - NIST-800-53-AC-8(a)
    - NIST-800-53-AC-8(c)
    - NIST-800-53-CM-6(a)
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - restrict_strategy
    - sshd_enable_warning_banner
OVAL test results details

Verify if Profile set Value sshd_required as not required  oval:ssg-test_sshd_not_required:tst:1  false

Following items have been found on the system:
Var refValue
oval:ssg-sshd_required:var:10

Verify if Value of sshd_required is the default  oval:ssg-test_sshd_requirement_unset:tst:1  true

Following items have been found on the system:
Var refValue
oval:ssg-sshd_required:var:10

package openssh-server is removed  oval:ssg-test_package_openssh-server_removed:tst:1  false

Following items have been found on the system:
NameArchEpochReleaseVersionEvrSignature keyidExtended name
openssh-serverx86_64(none)5.fc348.6p10:8.6p1-5.fc341161ae6945719a39openssh-server-0:8.6p1-5.fc34.x86_64

Verify if Profile set Value sshd_required as required  oval:ssg-test_sshd_required:tst:1  false

Following items have been found on the system:
Var refValue
oval:ssg-sshd_required:var:10

Verify if Value of sshd_required is the default  oval:ssg-test_sshd_requirement_unset:tst:1  true

Following items have been found on the system:
Var refValue
oval:ssg-sshd_required:var:10

package openssh-server is installed  oval:ssg-test_package_openssh-server_installed:tst:1  true

Following items have been found on the system:
NameArchEpochReleaseVersionEvrSignature keyidExtended name
openssh-serverx86_64(none)5.fc348.6p10:8.6p1-5.fc341161ae6945719a39openssh-server-0:8.6p1-5.fc34.x86_64

tests the value of Banner setting in the /etc/ssh/sshd_config file  oval:ssg-test_sshd_enable_warning_banner:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_sshd_enable_warning_banner:obj:1 of type textfilecontent54_object
FilepathPatternInstance
/etc/ssh/sshd_config^[ \t]*(?i)Banner(?-i)[ \t]+(.+?)[ \t]*(?:$|#)1

tests the value of Banner setting in the /etc/ssh/sshd_config.d file  oval:ssg-test_sshd_enable_warning_banner_config_dir:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_sshd_enable_warning_banner_config_dir:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
/etc/ssh/sshd_config.d.*\.conf$^[ \t]*(?i)Banner(?-i)[ \t]+(.+?)[ \t]*(?:$|#)1
Force frequent session key renegotiationxccdf_org.ssgproject.content_rule_sshd_rekey_limit medium

Force frequent session key renegotiation

Rule IDxccdf_org.ssgproject.content_rule_sshd_rekey_limit
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-sshd_rekey_limit:def:1
Time2024-12-29T17:33:56+01:00
Severitymedium
Identifiers and References

References:  CCI-000068, FCS_SSHS_EXT.1, SRG-OS-000480-GPOS-00227, SRG-OS-000033-GPOS-00014

Description
The RekeyLimit parameter specifies how often the session key of the is renegotiated, both in terms of amount of data that may be transmitted and the time elapsed.
To decrease the default limits, add or correct the following line in /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf:
RekeyLimit 512M 1h
Rationale
By decreasing the limit based on the amount of data and enabling time-based limit, effects of potential attacks against encryption keys are limited.

# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

var_rekey_limit_size='512M'
var_rekey_limit_time='1h'



mkdir -p /etc/ssh/sshd_config.d
touch /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf

LC_ALL=C sed -i "/^\s*RekeyLimit\s\+/Id" "/etc/ssh/sshd_config"
LC_ALL=C sed -i "/^\s*RekeyLimit\s\+/Id" "/etc/ssh/sshd_config.d"/*.conf
if [ -e "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf" ] ; then
    
    LC_ALL=C sed -i "/^\s*RekeyLimit\s\+/Id" "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
else
    touch "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"

cp "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf" "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak"
# Insert before the line matching the regex '^Match'.
line_number="$(LC_ALL=C grep -n "^Match" "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak" | LC_ALL=C sed 's/:.*//g')"
if [ -z "$line_number" ]; then
    # There was no match of '^Match', insert at
    # the end of the file.
    printf '%s\n' "RekeyLimit $var_rekey_limit_size $var_rekey_limit_time" >> "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
else
    head -n "$(( line_number - 1 ))" "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak" > "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
    printf '%s\n' "RekeyLimit $var_rekey_limit_size $var_rekey_limit_time" >> "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
    tail -n "+$(( line_number ))" "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak" >> "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
fi
# Clean up after ourselves.
rm "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak"

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Strategy:configure
- name: XCCDF Value var_rekey_limit_size # promote to variable
  set_fact:
    var_rekey_limit_size: !!str 512M
  tags:
    - always
- name: XCCDF Value var_rekey_limit_time # promote to variable
  set_fact:
    var_rekey_limit_time: !!str 1h
  tags:
    - always

- name: Force frequent session key renegotiation
  block:

    - name: Deduplicate values from /etc/ssh/sshd_config
      lineinfile:
        path: /etc/ssh/sshd_config
        create: false
        regexp: ^\s*{{ "RekeyLimit"| regex_escape }}\s+
        state: absent

    - name: Check if /etc/ssh/sshd_config.d exists
      stat:
        path: /etc/ssh/sshd_config.d
      register: _etc_ssh_sshd_config_d_exists

    - name: Check if the parameter RekeyLimit is present in /etc/ssh/sshd_config.d
      find:
        paths: /etc/ssh/sshd_config.d
        recurse: 'yes'
        follow: 'no'
        contains: ^\s*{{ "RekeyLimit"| regex_escape }}\s+
      register: _etc_ssh_sshd_config_d_has_parameter
      when: _etc_ssh_sshd_config_d_exists.stat.isdir is defined and _etc_ssh_sshd_config_d_exists.stat.isdir

    - name: Remove parameter from files in /etc/ssh/sshd_config.d
      lineinfile:
        path: '{{ item.path }}'
        create: false
        regexp: ^\s*{{ "RekeyLimit"| regex_escape }}\s+
        state: absent
      with_items: '{{ _etc_ssh_sshd_config_d_has_parameter.files }}'
      when: _etc_ssh_sshd_config_d_has_parameter.matched

    - name: Insert correct line to /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf
      lineinfile:
        path: /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf
        create: true
        regexp: ^\s*{{ "RekeyLimit"| regex_escape }}\s+
        line: RekeyLimit {{ var_rekey_limit_size }} {{ var_rekey_limit_time }}
        state: present
        insertbefore: ^[#\s]*Match
        validate: /usr/sbin/sshd -t -f %s
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
    - configure_strategy
    - low_complexity
    - low_disruption
    - medium_severity
    - no_reboot_needed
    - sshd_rekey_limit
OVAL test results details

Verify if Profile set Value sshd_required as not required  oval:ssg-test_sshd_not_required:tst:1  false

Following items have been found on the system:
Var refValue
oval:ssg-sshd_required:var:10

Verify if Value of sshd_required is the default  oval:ssg-test_sshd_requirement_unset:tst:1  true

Following items have been found on the system:
Var refValue
oval:ssg-sshd_required:var:10

package openssh-server is removed  oval:ssg-test_package_openssh-server_removed:tst:1  false

Following items have been found on the system:
NameArchEpochReleaseVersionEvrSignature keyidExtended name
openssh-serverx86_64(none)5.fc348.6p10:8.6p1-5.fc341161ae6945719a39openssh-server-0:8.6p1-5.fc34.x86_64

Verify if Profile set Value sshd_required as required  oval:ssg-test_sshd_required:tst:1  false

Following items have been found on the system:
Var refValue
oval:ssg-sshd_required:var:10

Verify if Value of sshd_required is the default  oval:ssg-test_sshd_requirement_unset:tst:1  true

Following items have been found on the system:
Var refValue
oval:ssg-sshd_required:var:10

package openssh-server is installed  oval:ssg-test_package_openssh-server_installed:tst:1  true

Following items have been found on the system:
NameArchEpochReleaseVersionEvrSignature keyidExtended name
openssh-serverx86_64(none)5.fc348.6p10:8.6p1-5.fc341161ae6945719a39openssh-server-0:8.6p1-5.fc34.x86_64

tests the value of RekeyLimit setting in the file  oval:ssg-test_sshd_rekey_limit:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_sshd_rekey_limit:obj:1 of type textfilecontent54_object
FilepathPatternInstance
1h
512M
^[\s]*RekeyLimit[\s]+512M[\s]+1h[\s]*$
/etc/ssh/sshd_config1

tests the value of RekeyLimit setting in SSHD config directory  oval:ssg-test_sshd_rekey_limit_config_dir:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_sshd_rekey_limit_config_dir:obj:1 of type textfilecontent54_object
PathFilenamePatternInstance
1h
512M
^[\s]*RekeyLimit[\s]+512M[\s]+1h[\s]*$
/etc/ssh/sshd_config.d.*\.conf$1
Configure SSSD to run as user sssdxccdf_org.ssgproject.content_rule_sssd_run_as_sssd_user medium

Configure SSSD to run as user sssd

Rule IDxccdf_org.ssgproject.content_rule_sssd_run_as_sssd_user
Result
fail
Multi-check ruleno
OVAL Definition IDoval:ssg-sssd_run_as_sssd_user:def:1
Time2024-12-29T17:33:56+01:00
Severitymedium
Identifiers and References

References:  FMT_SMF_EXT.1, SRG-OS-000480-GPOS-00227

Description
SSSD processes should be configured to run as user sssd, not root.
Rationale
To minimize privileges of SSSD processes, they are configured to run as non-root user.

# Remediation is applicable only in certain platforms
if rpm --quiet -q sssd-common; then

MAIN_CONF="/etc/sssd/conf.d/ospp.conf"

found=false

# set value in all files if they contain section or key
for f in $(echo -n "$MAIN_CONF /etc/sssd/sssd.conf /etc/sssd/conf.d/*.conf"); do
    if [ ! -e "$f" ]; then
        continue
    fi

    # find key in section and change value
    if grep -qzosP "[[:space:]]*\[sssd\]([^\n\[]*\n+)+?[[:space:]]*user" "$f"; then
            sed -i "s/user[^(\n)]*/user = sssd/" "$f"
            found=true

    # find section and add key = value to it
    elif grep -qs "[[:space:]]*\[sssd\]" "$f"; then
            sed -i "/[[:space:]]*sssd/a user = sssd" "$f"
            found=true
    fi
done

# if section not in any file, append section with key = value to FIRST file in files parameter
if ! $found ; then
    file=$(echo "$MAIN_CONF /etc/sssd/sssd.conf /etc/sssd/conf.d/*.conf" | cut -f1 -d' ')
    mkdir -p "$(dirname "$file")"
    echo -e "[sssd]\nuser = sssd" >> "$file"
fi

if [ -e "$MAIN_CONF" ]; then
    chown root:root "$MAIN_CONF"
	chmod 600 "$MAIN_CONF"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
OVAL test results details

tests the value of user setting in SSSD config files  oval:ssg-test_sssd_run_as_sssd_user:tst:1  false

No items have been found conforming to the following objects:
Object oval:ssg-obj_sssd_user_value:obj:1 of type textfilecontent54_object
FilepathPatternInstance
^/etc/sssd/(sssd|conf\.d/.*)\.conf$^\s*\[sssd\].*(?:\n\s*[^[\s].*)*\n\s*user[ \t]*=[ \t]*(\S*)1
Scroll back to the first rule
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